Most users got home at either mastodon.social or mstdn.social
So monetise contribution to these instances first.
Despite, mastodon.social is well funded but recent surge of new users must cost them resource.
It is advised new users to contribute to their respective home instance.
For donating to #Mastodon software development can be done later pace as instances requires financial support than development
I don't.
I am running an other instance which is quey.org.
Though, I am seeing a few making donation now.
Have you donated yet ?
Credit cards are fine.
Debit cards are pain.
Top private sector, ICICI, Axis bak, HDFC debit card, & SBI debit cards work fine for me.
Indian overseas, Indian bank, similar cards failing.
By the way, I use primarily #SBI debit card linked with Paypal for a few International merchants.
Though need to enable international transaction which I enable via Internet banking.
here is screenshot of SBI page to enable International transaction