To remember to wear your school uniform tomorrow, you can say "Remember to wear your school uniform tomorrow" or "Don't forget to wear your school uniform tomorrow."

Here are a few more ways you can say it:

"Make sure you wear your school uniform tomorrow."
"It's important to wear your school uniform tomorrow."
"Don't forget, you need to wear your school uniform tomorrow."

It's a good idea to set a reminder for yourself, such as setting an alarm on your phone or writing a note, to help you remember to wear your school uniform.