Start by filling it up with water... LOL!! Sorry..
Anyway let it sit for a few days with the filter and heater running. A good temp would be 77 to 82 or so for the best bacteria growth. Then after 2 or 3 days of that take some gravel from your 10 gallon and add it to your 29 gallon. You can do this anyway you wish.. I have heard people putting it in a nylon stocking for easy removal when you are done with it and so on... This will help to "seed" your tank. You can even use the bio-media fromt he filter in your 10 gallon as well if you'd like.
Now of course your 29 gallon will need to be producing ammonia for this all to work so feeding your 29 gallon take a few flakes here and there will help this process move right along. When you start to see the brown growth on your substrate, ornaments, glass, or whatever you have gotten towards the end and testing the water may be a good idea then.
I am sure others have plenty to add to this but it should get ya started.
