Option one, the simplest one.
Can't pay child support if you don't have children!


Pros - No children
Cons - This is most real option because noone will sleep with you anyway

The second and equally easy option
Just tweet @elonmusk and ask can you send your money on mars
It's 2022, he will probably agree

Pros - No money, no worries
Cons - You just powered up economy of martians and you doomed us all in race for space-oil

Make bomb out of the potato and piece of copper and become demolition man

Pros - You got job as a demolition man
Cons - You can't sticky jump

You can't pay child support when universe is ending.

Pros - Universe ended
Cons - Universe ended

This one may seem little hard, but it's actually easy.
Just add milk before cereals (you psychopath) and be loud and proud about it

Pros - ???
Cons - "Everyone bloody hates you" ~Demoman

Egg

Egg - Egg
Egg - Egg

You can't pay child support when entire planet is dead

Pros - Funki Monki
Cons - screenshot

Yeah, this idea is basically flawless!

Pros - free housing without payment, no taxes, a lot of fancy food like moldy cheese (or bread), a lot of fun people to meet.
Cons - Your ♥♥♥♥♥♥♥ will grow three sizes

There you have it.
At least three easy ways to avoid paying child support.

Hope you can now enjoy your uber expensive videogame items (you virgin, lol)