Question authors are asked to "Accept" an answer to let others know that you have received a good answer to your question (see the faq).
But accepting an answer too quickly has an unwanted side effect that it discourages others from improving on the early-posted answers. You should to allow enough time to let people provide the best possible answer and to let the voting and other activity take effect.
I would suggest waiting at least 24 to 48 hours before accepting an answer. That gives time for multiple answers to be offered. You should choose the best one, not simply the quickest one.
Users are guided by the behaviors they see on this site. Accepting an answer within minutes sends the wrong message.
Don't turn this into a race to answer first; but answer well.