2 cones at the end of the track, 60 ft apart... 2nd cone is the finish line. There's probably an exit right after the last cone... don't try to exit there. Just keep going, there will be a few more.
That's the main mistake I made my first time... I don't know if some tracks mark the finish clearer than others, but I saw an exit coming up and thought I had already finished... so slamming on the brakes I ran a 14.7 @ 70ish mph
If you are on street tires, don't roll through the water, drive around it. Don't do a burn-out... you can spin em for a half second or so just to clean them.
Launching just comes from practice. You can try dumping it at different RPM's, but on street tires, you're probably better off slipping it. I still don't have it down, and I haven't gotten to go on my drag radials yet
At first, don't worry so much about your reaction times as they don't affect your time on the time slip. Example, you can leave the line 2 seconds after the green light comes on and it won't add 2 seconds to your time.
Best mod is the driver mod at the track. You'll be amazed how much your times will drop as you continue going back to the track. First time there, don't worry to much about your times, just have fun and practice launching.