the idea is to use a low dose sarm alongside your serm and a test booster. you don't want to go too high on the dosing of the ost for the fact that it is slightly supressive. i've started 25mg the last week of cycle then dropped to 12.5mg for the first two weeks of pct along side 20mg nolva. third and fourth week 6.25mg ost and 10mg nolva. daa used throughout and a 25mg atd ed from wk3 until whenever it runs out to counter the possible est increase that accompanies daa after 3-4wks of usage. not a bad way to pct considering how little bf comes back on and how strength is so easily maintained.
as per pyrobatt said, you don't want to eat or train for mass in pct. ideally you want to drop reps and start to increase weights, a bit like power lifting. focus on the big 4 lifts (squats, bench, deads, pullups) and hit them once/week max. don't overtrain. you're only in pct training mode for a month, consider it a priming stage for adding a few more plates before switching up training again and gunning for mass. i was lifting 5x5's on cycle and in pct i'm lifting 3x5's. squats were so painful tother day that by the third set i was hitting a rep then racking until completion. as soon as i hit my reps i did 10min on the bike and got out of dodge. diet wise, if you gained a lot on cycle you'll need to make sure that you're eating enough to maintain that new mass. don't be tempted to over or undereat. work out your macro's and stick to them, especially for the first month. also avoid long cardio sessions, they could eat your new muscle. instead opt for a couple of hiit sessions. if you're eating bang on maintenance then you can theoretically get away without cardio for that 'cementing' month. i'd advise a couple of hiit sessions tho, or even just 10-15min interval training after your workout just to keep things moving. if you do start to get fat adjust the diet.
i am sure you'll all know the above as it's prolly been drilled into you since you started experimenting with different compounds so pls forgive me if i sounded patronising at all.