What is better to build muscle for bodybuilding, to start with the maximum weight that you can do and take off little by little? Or to start low and increase in weight? Also how many reps and sets should I do? Should I keep the reps and sets high or low?

try the lil jack workout http://www.youtube.com/watch?v=TKCGe2Ezris it really works
If you have zero experience lifting weights, then it is best that you start low and increase the weight and reps gradually. Try to increase the weight and reps bit-by-bit each week for positive progression.
As for the number of reps and sets…
Well, for beginners 2 sets max and 6 – 8 reps max. If you can do more than 8 reps, that means the load is not heavy enough. If you’re unable to do than 6 reps or more, that means the load is too heavy for you so drop the weights a little…
Keep it around 6 – 8 reps to maintain good form and optimal muscle fiber recruitment.
Good luck!
You should start from a low weight then slowly increase the weight until you reach the maximum so that your muscles could adjust. Visit http://top3fitnessprograms.com/ to learn more about the proper ways on how to effectively build muscles.
Hey Jose try lift as much as you can doing 3 sets of 8-10 reps. Generally when i workout I do sets of 10,8,8. If the weight is too light you’re not really working the muscle, and therefore not promoting muscle growth. I replied to your other post: “How can I make a bodybuilding weightlifting routine?” with my personal routine, that should help you get started.
Full body routines are generally best i find with my clients. Especially if they can only train 2 or 3 times a week.