Just remember this feeling of accomplishment, and do everything you can to burn in the memory and feelings you had working up to your first solo and how you felt after you did it. Think hard about all the good and bad things instructors have done during your training over the years.
Then never forget that as a CFI that's what you're making possible for others. It's what keeps you going when things get rough. Do what the good instructors do and kick your own ass if you start getting tempted to do what the bad instructors did.
My two cents..