Is it just as simple as mon - squat 3x10 leave thurs - deadlift 3x10, sun - bench 3x10 etc
What exercises should I add each day?
i do this type of lift per day sort of thing, if u want a better idea of assistance have a peek in my log...
now you say your doing PPP right?
for squat day;
squat PPP
GHR
reverse hyper
chins/lat pull down
ab wheel roll outs
bench day;
bench PPP
then maybe one or 2 of these; inclines, declines, dumbbells, close grips
chins/lat pull down
barbell rows
deadlift day;
deadlift PPP
light squats (when i do deads i will always do light squats after them, they feel like shit, but after them you feel better)
GHR
hyper/revers hyper extentions (id pick one or the other, but its up to you)
chins/lat pulldown
ab wheel roll outs
thats just rough outline of what you can do.
u can alternate assistance if u dont want to do the same exercises each night
if you still want to sub in working exercises such as military press or cleans, you can, but u just need you use your head for what night you do them on, like i wouldnt do working bench then working MP in the same night as one will hinder the other.