I have used Shawn's precise measurement with great results!
A few tips if I may...
Make sure the kiddie pool is the correct size before you buy it. Double check and make sure the kiddie pool is the right size before you fill it up

ask me how I know...
All of the frame must be under water and the pools come in 2 or 3 sizes. Buy two, as soon one will somehow get a hole poked in it (but save it - see below).
Remove any grease and grime from the paint first as the acid does not penetrate it well. No aluminum parts in the bath if it can be helped as it may turn odd colors and is probably not good for the paint.
Fill kiddie pool with warm/hot water, 80-85 degrees works well for me. Mix the OA in a gallon bucket of warm water (always add acid to water, not the other way around) and dissolve it and then pour it in the pool.
You can do OA baths outside in cold weather. All you need is a means to heat OA water in a large pot and recirculate it back to the pool as needed. If you bought an extra kiddie pool double them up for insulation by using the one with a hole poked in it on the outside. I use a $10 hotplate and a big crab pot out back of the shop to heat the water. I cover the water with black plastic garbage bag while it is soaking. I use a Dollar Tree thermometer in the pool and keep the temp at 80/85 degrees and I find 3 to 4 hours of soaking at that temp is optimal. It is a mild acid solution and does not bother my hands but if I have forgotten or was too lazy to glove up, I always wash up quickly.
Do not grab the bike by any decals when you are picking it up after soaking. When done, rinse with frame with plain water and then blow dry it with air compressor. WD-40 the inside of the frame and then blow out excess. Never damaged a decal but I always assume they don't want to be touched until they are bone dry again.