I personally do not, but I think it's a personal decision. I have a background in working for homeless non-profits. If you have a desire to really help and be part of moving towards a solution, find a local group and donate and/or volunteer with them.
The reality of handing money to someone is at best it's a band-aid, and more often you're just buying that night's substance of choice. No judgement there, if I was homeless and likely not receiving needed medical and mental health treatment, I'd be high and drunk as often as I could too. Hell, I'm high as often as I can be now. Nevertheless though, I feel comfortable choosing not to participate by handing money when asked and I don't begrudge anyone who does.
exactly how i do it, and i make sure 50% of my professional life i’m sacrificing income to work for not for profits. i want my donation to be the most effective it can be, and making sure that people have roofs over their head isn’t going to happen with my spare change