This all depends on your goals. Figure out what it is you want to achieve then design your training accordingly. What is your short, medium, and long term goals?
4 days rest per muscle group is generally the rule of thumb, just listen to your body thats the best way....ull know if youre overtraining, i like ot increase the volume of my workouts when "on" opposed to the frequency
to start just pick a good program that hundreds of people on this board have used and gotten good results. follow it 100% with great intensity. after 8-12 weeks switch up to another.. repeat
you will then know what program works best for you and can start switching
5x5 is good
wendler 5/3/1 is good
push/pull/legs good
if you start getting tendonitis or inflammation you need to back off. listen to your body. if your muscles start getting sore and weak then you need to back off. listen to your body. once you learn how to listen to your body you will understand what i am talking about. now if you want to take anti-inflammatories and aspirin and keep pounding away when your body is telling you it needs a break then you will end up with chronic injuries.
there is no rule to working out. I will work out the same muscle 2 straight days in a row. or i will work the same muscle every 5 or 6 days. there is no rule as long as you are seeing results.. now if you aren't improving then you need to re-examine what you are doing. it makes a difference what kind of shape you are in as well