Here's what my normal routine:
1. Cold crash carboy at 35 for 3 days.
2. Put weighted hop bags into keg, the seal it and purge with CO2. I use about 3psi - pressurize it, open valve to release, then repeat several times.
3. Transfer cold beer into keg, making sure tube is long enough to go all the way to the bottom of keg.
4. Put lid back on keg, and purge the head space with CO2.
5. Check temperature - I don't open it up again, I use a temp strip on outside of keg. It's usually at around 45degrees at this point.
6. Pressurize to appropriate level based on temp and co2 volume needed (usually around 14psi or so).
7. Lay keg on it's side and roll back and forth for several minutes to force charge. Doing this also ensures the hops get nice and wet, and I like getting carbing out of the way.
8. Let keg sit at room temp for a day or two.
9. Put keg in kegerator at 50-55 degrees for 2 weeks or so.
10. Drop it down to 35, reattach CO2 and pressurize at 10-12psi or whatever is required for temp and level desired.
11. Drink or bottle sometime in the next several days to a week, leaving the hops in the keg the entire time.
You can get a grassy flavor from the hops if you leave it in the beer for too long at room temperature, but at lower temps, you won't get that. Best to leave it in the keg the entire time.
I get very good aroma doing this. Also, I always dryhop with a minimum of 3 ounces.
I like to carb it and shake it up right after going into the keg, then after that it just sits there and any sediment has a chance to drop out - especially after the 35deg period.
Everyone does it differently, so you should experiment with various methods and do what works best for your setup and tastebuds/nostrills.
