Hmm, I don't know that I have an actual strategy. What I do is kind of random. But I think there's this subconscious limit that makes the money go out more easily if I am under a certain limit. By the way, charity for tax purposes is very restricted in the Netherlands.
For the people on the receiving end the 'charity' can work out substantial. Like living rent free for extended periods. But I must say that I can get annoyed with people not using the opportunity they are given. Like not improving themselves as they don't have the burden of paying for a roof over their heads.