I have owned handguns since the early 80's (except the past 20 years I spent in New Yuk)  I have never carried concealed.  so recently I bought a Sig P-320 compact for my carry gun. here is the issue the best I can describe it...
I am right handed, about 5-4 145#  jeans and t-shirt guy, sweatshirt and Carhart jacket when it gets cold.  I do not wear large or baggy anything, and also do not wear a belt.
I cannot fit a IWB on my right side or front, I did buy a left hand leather IWB for small of the back carry... which I really like, but my shirt does little to conceal the hump.  anyone else with similar size and dress style that can help?  
at 50 I really don't feel like changing how I dress just to conceal.  thanks for the input/help!

I know you said you do not wear belts, but it really makes a difference. I have carried for 3 years now and started off with just a standard leather belt. After a couple months of that I bought a Ares Ranger Belt (but I think any rigid belt would do) and it makes a HUGE difference in how the gun conceals. I easily conceal a Glock 19 in shorts and a t-shirt when I use that belt.

Another thing that helps is the right holster, this I am still figuring out the best for my uses as its different for each person. Currently I am using an Aliengear 3.0 holster and its pretty comfortable, I will probably go with Stealth Gear next.

I'm about your age and only a little bit taller and heavier than you.
You're going to have to make some wardrobe changes whether you like it or not if you want to carry a gun concealed.
A good, quality gun belt is a must as a starting point. Even if you end up pocket carrying a smaller gun a belt makes a huge difference.
If you're going to carry IWB you'll probably need some britches slightly oversized in the waist.
SOB carry is generally not recommended as it poses a number of problems.
T-shirts can work fine as cover garments as long as they aren't form fitting around the waist line and are long enough. But I've had better results with slightly larger short sleeve collared shirts untucked.

Carrying a gun on a regular basis requires several lifestyle changes for most people, wardrobe being one of the biggest. It doesn't have to be uncomfortable at all; but it's meant to be comforting, not comfortable.

My recommendation is to keep trying combos until you get a system that works for you. Everyone's comfort zone and needs are different, one person's solution may or may not work for you. But keep at it please and be another responsible person out there armed and ready. Good for you for making the choice to carry .

Cheers!
-JC

You want to carry a P320 without a belt that is not going to be fun.

Like mentioned get a good carry belt.  I have an Ares Gear Aegis belt and I got it over the Ranger because I like how fast I can change the tension on my belt tighten and loosen as need.  Second it is much less inconspicuous with the buckle design.  

You can have a great holster and no or crappy belt and carrying will be difficult or uncomfortable.  You can have an alright holster and great belt and your life will change as far as carrying goes.  Couple a good belt with a good holster and your life will never be the same.

So to recap get a good carry belt.

Thanks for the great advise guys... I guess I'll be looking into belts!  it really does make sense... It's just a lack of knowledge in this area  I have..

We all start somewhere.   I have a box full of holsters that I found do not work or just lacked in certain aspects or did not hold up.  Same with belts I have tried a lot of belts and holster combinations of the years.

Best belt hands down for carry is the Ares Gear Aegis belt.  I can quickly and easily adjust the tension and it is working on over 2 years old since I got it and still not showing any signs of sagging like every other belt I have tried.  I gave up on leather because no matter what is eventually starts to sag and belts that have static holes for size adjustment just do not work especially being a slender guy I have no curves.

I am a lot like you; older and particular about the clothes I wear and the “look” I want with my wardrobe.
Additional issues; I am a “shirt tucked-in” type of dresser most of the time.  AND I live in PA which means highly variable climate and weather conditions; 100 degree highs in the summer (along with 80% humidity) and 0 degree lows in the winter.

Guess what?
I made a few changes.
Had to.
It’s unavoidable, especially for me because I need to carry without printing because effective concealment is just mandatory in my work environment.

For me, all of the above meant that I need two concealment weapons (and both need to be small) and several holster choices for each in order to effectively conceal under the wide range of conditions I need to deal with.

So, the “trick” is to make wardrobe changes that you can live with and/or “get comfortable” with.  Some things are easy and represent no real change at all.  For example, because IWB works very well for me, I buy jeans with one more inch in the waist.  Jeans are not a problem because they are made in different styles and cuts.  You can easily find jeans that still look trim and not baggy, but that are just a bit larger in the waist.  I have bought some different trousers.  For me, this was a big deal.  I like jeans and have worn them all my life.  But now I usually wear Carhartts to work because they have roomier pockets that work well with a pocket pistol/holster combination.  I still don’t like them especially, but ya gotta make SOME concessions.  
I have bought several cardigan sweaters.  Cardigans make GREAT concealment accessories, because you can open them instead of taking them off when you get too warm.  I always hated cardigans; I am a crew neck guy.  I have always associated cardigans with “geeks” and “old men”.  Well guess what?  I may not like the idea of it, but I AM an old man now.  A lightweight cardigan works very well with an IWB and a heavy cardigan works perfectly with a shoulder rig.  (A handgun behind a heavy cardigan can be accessed if you leave a couple of the middle buttons unbuttoned. And a heavy cardigan CAN be “cool”….check out Steve McQueen in “Bullitt” with his heavy weight, dark maroon cardigan).  
I have also “discovered” Hawaiian and Guayabera shirts (two MORE styles I have NEVER worn before).

For me, carrying concealed has involved a lot of thought, some “attitude adjustments” and there has definitely been expense involved in making wardrobe adjustments.  But I am a good ccw artist at this point; I’m comfortable with my appearance, and proud of what I have been able to figure out.

Lastly, none of your clothing is worth anything if you cannot access and draw your weapon.  It is important to check all your ideas out on the firing line and to practice with it all.

1. Get belt
2. Get OWB holster
3. Carry

At 5'4" your beltline is below most people's line-of-sight.  Even if there's a lump almost nobody will notice and the ones that do will see a lump so who cares.

This post nailed it.

OK ..thankyou for all the suggestions and input! I went out and bought a few pair of jeans a waist size bigger than I wear now...I also bought a decent belt to start. then this morning after doing some research I ordered the alien gear cloak tuck 3.0 IWB holster.  I figure like mentioned above.. it's all trial and error and  I expect I'll be changing things as I go!  
I spent years in the building trades wearing a tool belt... took me a while to get a set-up I liked and felt good.. to this day I can put it on and my muscle memory takes me right everything I need.  I hope this goes as well.

If the extra pant size becomes annoying, there are stretch fit jeans that will expand about a size and a half. Roughly the size of a gun and holster. Wrangler makes a very comfortable one. I can't stand having my inseam baggy!

Ares gear is where it's at for belts as mentioned. I like the Ranger better than the Aegis. It's just a bit stiffer, which I prefer.

well ... after ordering and receiving the alien gear IWB holster buying pants that are too big.. I have decided that IWB is just not for me..I am never going to be comfortable in clown pants... just to get the holster in I had to buy a 32 waist.. I am a 29 waist...  I did buy a good belt,  and I guess my next step is ordering a good OWB holster.  thanks for the help though

This/\/\/\/\/\/\.....   great advice I missed...

IBX Tactical does kickass kydex. I recommend getting the pancake wings, they really help keep the holster closer to the body.

Ankle holster?

Gun belt and "bowling" shirts, works for me.

If you are Charlie Harper