here is a Photoshop template that i made to make easy to crate some costume dot view background
as you know after the last update of dot view app you can set a costume background but some template and Photoshop work need to make nice one.
after opening the file you must set a grid size every 200 pixel and subdivision every 5 in Photoshop preference/Guide, grid...
then use Snap and tic Grid in View Menu
after that use Rectangle tools to draw your own background.
because of exact size of template the drawn thing exactly fit the Dot View dots.
some of my work like Super Mario and my name included in template to help you.
finally save file as JPEG and copy it to phone and use it as Dot view background like me :)
PSD Template file link: