A hint: upvoting a story creates an entry in the "saved stories" link that is part of your profile.
In general I digest a lot of information partially and much of it slowly. It's addictive, and for a while I used "noprocrast" but that was a long time ago.
Anyway, I read what I read and don't bother worrying that I missed something. The first order value of HN is breadth, and less than everything still broadens my knowledge and understanding. Nobody can read all the good things, never mind read everything.
Good luck.