How to care for a Bonsai Tree?

Wow!! Your bougainvillea tree is gorgeous! If you can do that I would definitely go for a bonsai!

Here you go , this should help

http://homeguides.sfgate.com/make-bougainvillea-bonsai-21056.html

All the ones I've had were 75 years or older, done by a master Japanese gardner, generally you mist them 4x a day. You don't want what little soil there is to get wet, water only when dry and vary sparingly. Whatever the amount of light the natural plants needs, you do with your bonsai. We put them on little shelves on our fence in the garden in good weather. Bring them in at night and once weather cools for the winter.

Since bougainvillea are a vine, I would take 3 very small flexible little plants and train them to twine around each other....they do this with ginko trees.... very beautiful. Saw one at a NYC bonsai show belonging to Robert Mitchum that was 18" tall with 3 trunks twisted that was 250 years old. Gorgeous. https://www.bonsaiempire.com/blog/trunk-fusion

Good luck bonsai are very labor intensive. https://www.pinterest.com/pin/412220172121488195/

Get "The Complete book of Bonsai" by Harry Tomlinson, if you can find a copy. It's the best book on the subject out there and contains all the info you need. It's also packed with gorgeous photography - very inspiring!

I'll be watching this thread for hints as my son gave me an Azalea bonsai for Mother's Day.

I would just call Mr. Miyagi .

I am sure there is plenty of information on the internet but I suggest you join / seek out, a local Bonsai club that way you will get the best knowledge from the experts.