As long as you were in AHCI mode in your BIOS when you installed win 7....it installed the MS drivers for ya. So no worries on that front.
If you want to run a manual trim all you got to do is download ocz gc tool or what was called "wiper.exe" and run it. It will trigger what is for all intents and purposes a manual ITGC to be initiated. The longer it takes to finish...the more dirty your drive was. Best time to run it is right after you reboot and your OS is finished loading all its "stuff".
You can Dl it here:
OCZ Technology
Please note while it is close to 100% safe...its NOT 100%. I have only had it mess things up ONCE on me. If you are running 64bit OS its slightly higher chance of it going south than the 32bit...but like I said it only went south on me ONCE in all the times I have used it and it was as simple as run a fix mbr to get it back up and running. YMMV.
Run it once a week or 10 days'ish and you should be good. No need to run it everyday or anything...unless you are a benchmark junkie:)