300 is going to be nothing in the big picture, but its better than going in blind.
i would configure you hud using the "combined stats" feature.
this combines 4 different stats across each line, and if you stack 3 combined stats rows, you have 12 unique stats on each villain.
you can personally put whatever you like, but something like
Combined 1-
VPIP, PRF, CC, and total hands is a good first line.
Combined 2-
Cbet %, Folds to flop bet %, Steal Attempt %, Folds to steal Attempt %
Combined 3
fold to turn bet %, fold to river bet %, and whatever else.
im using a different comp, so i forget all the options off the top of my head, but basically
the first line is 4 basic categories, how much he's calling, raising, and total hands played.
second line is flop aggression, turn aggression
third line is river aggression and misc stats
as for how to interperet these stats. vpip. the higher the number, the looser the player, the more money they are leaking *unless they are running super sick. but anything in 6-9 max over 65 is way too high, they are playing a lot of junk, and you should raise whenever you enter a pot with them.
if its low, say, under 18-20%, they are being knitty and you should be stealing their blinds when the opportunity arrives.
raise percentage shows alot about people, just as vpip does. if they are maniacs with a high raise percentage, then re raises, and re steals come into play.
if their raise percentage is low, that means they are playing tag, and you should be playing hands in position with them, giving them credit for not playing as much garbage.
just a brief over view. there are some good websites that go more in depth.