A short list of items I have been required to do in the past to help "remind me."

Not wear certain articles of clothing.
Wearing certain articles of clothing I normally wouldn't.
Dressing with him in mind and to please him. (Showing perhaps a bit more skin then I would normally.)
Diet restrictions.
Speech restrictions.
Physical restrictions such as not sitting a certain way, etc.
clamps/dildo's/vibes at assorted times throughout the day.
Masturbating on a set schedule or when a certain thing happens (such as using the restroom) with or without being allowed to orgasm.
Restroom restrictions.
Set email schedule of things to look for/do and a timeline during the day to contact him.
Writing somewhere on my body. (Even though it may not be seen all day, the knowledge that it is there has an effect.)
Wearing a certain pieces of jewelry.

Actually, it can be just about anything... depending on how intense you want it.

YIM me if you want more details! Good luck to you two!

Hugs!
Annie