What is your goal? Size, or more of an all-around build=respectable size, but have endurance?
For size, you should always do one or two warmup sets to get some blood into the muscle and not to hurt yourself. 4-6 reps. If you get 7, add weight. If you get 3, take some off. 3 sets to failure or near failure. Slow eccentric motion. Some people go faster as they tire and barely do a half rep. 10 sorry reps is not as good as 3-4 great ones. If you don't have DOMS the second day after lifing, you did not create the microtears that it takes to cause repair and growth.
If you want an some gain in size and still have good stamina, do 8-12 reps and add cardio. Most people do the "prison workout"--do bench press and bicep curls. They have large pecs and large biceps. Small lateral and posterior delts, smaller triceps, no legs, cannot do pullups with their palms facing away which requires back strength. Do the things that you see few doing--because they are hard, but give good results-like wide grip pullups, pushups with your hands under your sternum and your feet wide for stability. Dips for your chest and triceps. Close grip and reverse grip bench press that will increase your tricep strength and thus increase your bench. Wide grip upright rows for your lateral delts. Shrugs for your traps. Don't get into conversations that distract you for periods of time. Fatigue more muscle fibers with each set and before all can recover, hit them again and recruit more that did not contribute before. Change your routine every few weeks. The body compensates and you will plateau. To increase your best lift or increase size, you have to add weight or reps. It is good to do both high and low rep workouts to hit all muscle fiber types-fast and slow twitch.
Having said that, and hopefully, you don't have a headache. I do two hours of cardio every other day and one hour after lifing free weights. Do your anaerobic work first. Always stretch. I am 6'1", 205,and start out with 225 on bench for warmup and currently max at 340 for 3-4 reps. I do sets of 20 for dips with 25 pounds hanging from a belt, and 10-12 pullups the same. People who read magazines will tell you to get bigger or be stronger, you cannot do cardio. Those people are lazy and get dizzy after squats because they are cardio insufficient. They cannot swim or run, bike or play multiple sports. They are bulky slugs with high body fat content and are smooth, not ripped. They are not all-around athletes. You will see them do a set of 4 heavy reps and walk around 10 minutes talking and trying to catch their breath. They may be on steroids and about to have a coronary. Don't get caught too close, cause whent they fall out, someone may want you to do mouth to mouth.
You need to see what you want to look like and what you want you body to be able to do. You also need to be realistic about your genetics. A short guy isn't gonna stretch, and a tall thin guy will have more trouble adding large amoount of bulk. I always liked decathletes and pentathletes as they can compete in many sports and do well. Finally, if you go to a gym, do your thing. Don't let someone tell what you should be doing. Meaning go slow and don't get hurt trying to prove something to someone that doesn't matter.