The most common/annoying mistake I have seen newbies doing in the weight room is benching and doing curls three times a week. First off, you’re only hurting yourself doing that. Your body doesn’t have time to recover from that much work. Secondly, that’s a horribly unbalanced routine. Who wants a big chest and arms and no back or legs? Third, you look like a douche doing it that much

You need to be on a completely balanced routine of working each muscle group once a week. Perhaps a Monday/Wednesday/Friday split of Chest/Tri’s, Back/Bi’s and Legs. That’s about as basic as it gets, unless you Do a full body twice a week on Mondays and Thursdays.