With your unified purse, you automatically have a functional payment page, where you could simply direct people to make payments for your donations or any other cause.
Your Donation URL/Link
Direct your audience to: https://unifiedpurse.com/donate/USERNAME
You can even add a short description to the URL, (just make the description url-friendly)
e.g https://unifiedpurse.com/donate/USERNAME/Development+of+our+area
Your General Payments URL/Link
Replacing /donate with /payment in the above illustration equally works.
E.g: https://unifiedpurse.com/payment/USERNAME
Replace USERNAME here with your actual unifiedpurse-username