I have to read my F-list starting from the point I left off last time. Reply to personal LJ and short fics as I go. Printout longer fics to read later because I cannot read more than about 1000 words on line and really absorb it. Usually I can't do any of my own posting until I'm caught up. Then, I do comments to any fics I took home for reading the previous night or over the weekend. And after that I go back to the various Comms that I'm currently raiding for old Dr. Who and Torchwood fics that might interest me, although I'm not going quite as whole hog with that as I did when started reading

I don't always comment on your personal LJ's but if you're on my f-list, I'll at least look.
Housefics I generally read those by writers I already like and a good summary can still grab me. I'm much much less likely to read anything that doesn't have wordcount in the header. Multi-parters? Fuggedabout it.
How do you do it?