The biggest strategy is to make sure you get an entry into the sweep before it ends.
I tend to pre-screen the new stuff on a daily basis and dump the stuff I want to enter into a mysweep category (since I'm plus, I have a custom where I also dump all the 1x FB, CD, DVD, Book entries too, but the regular one worked fine before I upgraded). And then I sort and enter trying to stay as far ahead of the expiration dates as I can and remove them from mysweeps as I go. It's nice to watch that number drop and I've gotten it down to 0 a couple times, but with as many 1x's that are added every day (+ the 1x that are in those other categories) it's not easy to keep up with and I usually have a few hundred with further out expiration dates that linger for a while.
I also will look through the list on occasion and make sure I enter the 1x that have daily or weekly prizes earlier rather than later.
So, that's more of an organizational strategy that a strategy strategy, but it works for me