Day time tips

For daytime you cannot rely on lighting so you have to make the props look a bit more realistic. There are a lot of how-to's on this and other sites on realistic painting of props.

Daytime also reveals things more so you can use more spiderwebs and such.

If your TOTs are only going to be little kids, then you need to tailor your setup to that age group too. Making it more fun rather than scary lets you make Halloween fun and inviting for the next generation of haunters.
Even simple things like having two or more tombstones have an argument by stashing some speakers in or near the stones and running a tape or CD for the sounds. Maybe Halloween themed jokes or riddles and name calling, singing, etc.
But as already mentioned, because you can't use the dark as part of your setting, you need to make the props and setup more realistic. People will be able to see everything pretty clearly.