Well at least you admit that you do not know what you are doing. Most people just stay in the gym continuing to do things wrong.
It is somewhat difficult to explain in writing how every exercise is properly performed. I have to say that seeing the trainer for at least one or session(s) would not be such a bad idea. You may want to tell him to show you how to do several different exercises for each body part. Tell him to stick to the basics (bench press for chest, curls for arms, etc.).
Don't be afraid to ask others questions or for help. I never have a problem with someone asking me how to properly do an exercise or even what muscle an exercise is targeting. Also, watch other people. You can intuitively tell who is doing an exercise right and who is doing it wrong.
When we mean go slow we mean go light on the weights. Try doing 15 repetition for every set. Since it sounds like you are totally new, I suggest picking up very light weight and lift the weight slowly. The goal would be to learn the proper motion, or form, of the exercise.
For example, if you wanted to work on your biceps grip the barbell with both hands at least shoulderwidth apart. Do not put any weight on the bar. Keep your elbows tucked into your body. Now lift the bar without swinging your body (no hip or back motion). Try to squeeze or flex your arms as the weight comes up. Then lower the weight as slowly as possible. Do this fifteen times. Remember to concentrate the whole time on your biceps and make sure no other part of your body is coming into play when doing this exercise.
Now when I say to hit a particular number of reps, I mean to try to get to that number using as much weight as possible without giving up form (later you can learn about forced or controlled cheats but lets keep it simple.
). So for 15 reps, you should use as much weight as will allow you to get to 15 reps with the last couple of reps being difficult to do. If you get to 15 with no trouble, add some weight. That least rep should be difficult to do.
After your body gets accustomed to this, you can start using heavier weights. For me proper form is key. If your form is off, you are not properly targeting the muscle group and are not efficiently breaking down the muscle. Learn form and then move weight; don't be so concerned with how much others are lifting.
For proper routines and diet do a search on this site. If it works, great; If it does not drop it. Don't be afraid to try something different. As you work out, you will learn more and will be changing things on occassion anyway.
I hope this helps.
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