im wondering what are some good combos to work out with for example. some people do legs and abs the same day...  i do shoulders and back the same day.
 and tomorrow im suppost to do arms and chest. but i realised that if i do my bi's and tri's by the time i start chest i may be to weak to get a good chest work out because the secondary muscles hit ( bi's tri;s) will be exhausted , so im wondering what combos u guys do!
 
also how many sets per exercise , i do about 3-4 sets , is that right? its only my second week im so frustrated and confused , i know ive gotta change the exercises up in awhile to confuse the muscles and i only know so many even when i look them up i forget ahh so confusing , anyway thanks for the help guys!

    Chest and Tri
Back and Bi
Shoulders and Legs
Ab's and Cardio

do 3 different exercises for each muscle (6 total)  I always throw in 1 ab exercise with 2 sets and then on my Ab day I do it normal.