This is pretty easy. Just reply to this email and put your notes about each check-in *below* that venue's name.
Leaving some blank is fine.
You can visit http://lastnightscheckins.com/notes to see your notes later on.
++ Nov 27, 10:49 PM @ Fat Tuesday's (ZQS3540) ++
++ Nov 27, 10:45 PM @ Planet Hollywood Resort & Casino (CpY3541) ++
++ Nov 27, 04:43 PM @ Las Vegas mini gran prix (94N3426) ++
++ Nov 27, 04:11 PM @ Pole Position Raceway (6jL3427) ++
-*-*- end email -*-*-
Don't forget: http://lastnightscheckins.com/maps/25490185246 has a map of all your check-ins to date!