100 Days to XMAS! Starting tomorrow! (NZ time)

I want to set myself a 100 day challenge!

Tossing up ideas on what I could do..

Maybe eat at least one fruit a day? (I’m not big on fruits)

Or a at least 20 mins of cardio each day…

OR a pushup a day, and +1 every day? (I can’t imagine being able to do 20 pushups, let alone 100!!) — Proper ones, not girl ones.   

Are you going to do a 100 day challenge? What are you gonna do?