Is it to pick one or two projects I particularly like and give there? Or donate to a large foundation like the fsf and let them spread the love?
Also, GitHub has a service too.
Foundation money goes mostly to the foundation so I try to send the money directly to the project
But anything that is "direct" for donations results in problems - by directly, I mean not going through a fee-eating third party that middlemans it. For example, numerous developer that I try to support with PayPal I will get the error "this payment can't be completed due to regulations" - apparently it is not possible to send to certain countries with paypal. Also known as: the places where those developers need it the most, compared to US/EU.
And for US banks, even sending small amounts to numerous western EU people all over the place near instantly triggers "cancel your card for fraud" safety checks.
The easiest way that is the least troublesome would be to donate to FSF or similar - but this means I can't choose where my impact goes, and the people whose software I use are likely to never see a sixpence of that donation.