In reply to mila: Hi Mila.
Ask the wall first, but essentially you want to put a carabiner through every bolt and aid off that. It means you will not damage the nylon tape on the insitu quickdraws at most wall. Generally the bolts are close enough together to aid at a wall but you will have climb normally to the first bolt.
It it actually a really good place to learn, as you often have to top step to make the distance between bolts. You also get loads of practice in the process of aid climbing. I run 'How to Big Wall' courses in Wales and the first day is all done in a indoor wall. Mainly because the amount of really good practice you can do.
I wrote an article for climber last year, have a look for it. It was a two part series the most important part for learning was part 1. I think is was imaginatively called "how to Big Wall Climb - part1"
As well as aiding consider practicing jumaring, jumaring deviations and jumaring horizontal traverses which are exactly the same type of problem you get jumar across roofs. If you are interested in a course.
http://snowdoniamountainguides.com/HowToBigWall.php