This is a test of commonsense. Complete the next sentence:

How to stop sucking your thumb (older kids )
Have the willpower to know you want to stop and think of a reason, like getting embarrassed at sleepovers.
Something along those lines should help.
Prepare yourself.
You probably won't sleep too well while trying to stop because you always sleep with your thumb in your mouth. This may make your mouth dry so keep a drink by your bed.