I went last year and if possible stay at the Sheraton Pasadena..it's connected to the convention center so no need to pay for parking. PLUS if u buy too much u can easily go back to your hotel room and drop off your stuff and go back in.
Now, it's freakin overwhelming SO i suggest u "study" the map and highlight the vendors u want to see the most. MAC, Sigma, OCC, Sugarpill, all the popular ones will have lines and guarantee to sell out on items. So if you want any of the popular brand ones i suggest u hightail it to that vendor right when u get in the doors. I was in line outside for maybe an hour or so and by the time I got to those booths it was pretty packed. Some are more organized than others...line vs a cluster of people. One of the most underrated booths is Naimis or something like that. Different brands like Mercier, Smashbox, Too Faced for 40% off!!! Plus what they do is grab the items for you, put it in a clear bin and hold it for 2 hours while u can either look for more stuff to add OR wait in line to check out.
I unfortunately can't go this year since Justin Timberlake has a concert that weekend and I scored amazing seats but if you have any questions, u can PM me....have a GREAT time!!!