how can i create a custom wallpaper? i know how to download them but i want to create a new one

I have a NEW 3DS

wanna be my friend? i'm use 2ds. my friend code is 4569 - 4051 - 9202

Today's my birthday!

Lets thank pretendo fot givingud this

pretendo is the best form of social media

add me bc i wanna play with some1 4421–8424–5630