Go to the dealer your going to buy your materials from and ask for product bulletins on all the products your going to use.
They will tell you application procedures, fluid tips to use, air pressure, coats, dry times, tape time, dust free time, reduction charts, compatible topcoats and undercoats, eveything you need to know.
As far as primers, for a primer surfacer, spray and let dry usually 4 hours, unless reduced then its 2(PPG K36 primer) then sand with a DA and 320, or block sand with 320 grit paper, once you get all the orange peel out of the primer and its smooth, then wetsand with 500grit paper, and then its ready for basecoat. If your primer sits more than 24hrs you will have to rescuff it, scotchbrite works well for that. Always spray basecoat until hiding, usually2-3 coats and then clear with another 2 coats minimum.