I'm in the same boat as you. I've never grown any autoflowering strains before but decided to purchase some Fast and Vast auto's and got some NL x Big Bud auto's as freebies. I'm also doing my photo plants but wanted to give the auto's a try in hopes of an early harvest to hold me over until Sept-Oct for my regular harvest.
I germed my autos and stuck them in 3 gallon pots (I lined them with newspaper but poked holes in it where the pots drain holes are). That's how I do it with my tomato plants for my veggie garden every year. I just used my normal soil mixture which is screened native soil, high quality topsoil with perlite, compost/ composted manure, a little sand for added drainage and peat. Since they just germed I don't have any other info for you yet but I plan on transplanting like normal hoping that I can just lift them out easily with the newspaper and slide them gently into their holes without stressing them too much.
I've been keeping an eye on the forecast and it looks like rain for the next couple weeks where I'm at. (about 39N) Looks like I'm going to have to veg them indoors longer than I expected.
Good luck on your grow this year!