illustration (attribution, if any possible, is at the end of the article)
Westerners love to think they can pick and choose… bad habit from unexamined consumerism! So of the eightfold path, they go straight to the 7th (mindfulness) and 8th (concentration) spokes; of the 6 pāramitā, they go straight for the 6th (wisdom). Bad habit of Western arrogance, mixed with the delusion that freedom lies in letting unexamined impulses/desires dictate one's next move/goal/practice!
And yet, the instructions are clear… and refraining from doing as one pleases is the beginning of a wider practice (much based on restraint)!
Generosity / dāna is the first pāramī(ta) in Buddhism, both in Theravāda and Mahāyāna schools.
And no excuse (most people invent some reason or another not to give) changes this fact.
The person typically praised in suttas and other texts is thus:
« Now, at that time, in Benares, a certain brahman of great wealth and resources was a well unto recluses and brahmans, indigents, tramps, wayfarers and beggars, gave away food, drink, clothes, lodging and other benefits. He ordered his life and gave, according to opportunity and as was fitting, to those coming and going, everything necessary for the road. »
— excerpt from book II, story 2, in Gehman, S: ``Stories of the departed'', in "Minor Anthologies of the Pāḷi Canon, volume IV", Pāḷi Text Society (1942)
Such a praise includes the two key angles to consider in order to start / keep / maintain a constructive practice of dāna / generosity.
The first angle is to remember (stay mindful) that, by taking care of oneself one helps others, and by taking care of others one takes cares of oneself… Giving so much that you will later require help from others is usually unwise: you're displacing a problem rather than reducing/solving it.
But giving little does count, generosity is not about excesses.
« Even when there's next to nothing, giving is good. » — SN 1.33
The second angle is to remember (stay mindful) that it's not about you!
« For generosity, nothing to do; other than stop fixating on one self. » —Milarepa, “song on the Six Perfections”
If you can give a lot but only a little is needed, just give a little (it's not about you shining!)… then help elsewhere with the rest! Wasting / splashing resources is not 'generosity'.
The mirror situation exists of course: give as much as you can (but still in accordance with 'first angle' above), and yes this requires effort and the said effort is indeed indicative of a genuine 'practice', of 'right effort'. Giving what you don't care about losing, what costs you nothing, is not yet 'generosity': it's not about you staying comfortable, and genuine practice is meant to shake one's attachments and fears (incl. the fear of missing)…
« having given the donation attentively, having given the donation with his own hand, having given the donation thoughtfully, having given the donation not as if he were throwing it away… » — DN 23
« If beings knew, as I know, the results of giving and sharing, they would not eat without have given, nor would the stain of miserliness overcome their minds. Even if it were their last bite, their last mouthful, they would not eat without having shared, if there were someone to receive their gift. But because beings do not know, as I know, the results of giving and sharing, they eat without have given. The stain of miserliness overcomes their minds. » — Iti 26
cf. also dāna sutta, on consequences attached to various intentions behind giving: http://www.accesstoinsight.org/tipitaka/an/an07/an07.049.than.html
Buddhism has no specific guideline on supporting teachers, it simply asks for you to consider causality: if you want this living tradition to survive, how are you participating, in practical terms, to make this happen? Nice words, exposure or social media ‘+1’ might feel good, but they do not actually help with the basic necessities: http://koan.mu/donate.htm