i'm trying to set up my tipping screen and I've done a few mark trial payments, and no tipping screen pops up
It would be helpful to know what version of Square you are using and what type of device.
Typically, you would go into settings on your device and then to Checkout settings and then choose tipping and create your settings.
Here is what the screen looks like on the Standard POS on a mobile device after clicking More -> Settings -> Checkout -> Tipping
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