You can start by reading this site:
http://johnlsayers.com/Recmanual/index.htm
you should also check out this site and take a look at some of the construction methods demonstrated there:
http://johnlsayers.com/Studio/index.htm
and also the forum rules for posting (click here).
The drawing programs we use are
http://sketchup.google.com/download.html
and http://www.smartdraw.com
You will NOT be assisted on this site if you:
1. Don't fill in the Location section in your profile - this is an international site and we need to know what country and city you are in.
2. Put up a post saying "I have a room X feet x Y feet - what should I do?"
3. Put up a plan that has no dimensions and does not point out pertinent facts like there's a pole in the middle of the room and the right hand wall is all glass.
4. Post pictures greater than 1200px wide.
5. Don't explain what you want to do within the studio - how loud you play, what kind of recording setup you have etc.
6. Don't explain how much isolation is needed because of neighbours etc.
Please also read the "Don't Post" articles specific to each forum before you post.
Welcome to Recording Studio Design.
If this site helps you design and build your studio there is a Donate button on the main page - please use it.
cheers
john