PLEASE HELP What size Motorcycle is the best for a Female?

[dolphingirl7404]

I am a female and have never been on a motorcycle but I really am interested in getting one and riding so if you could help me that would be great. I am fixin to be 25 and I am 5'10 and weigh 190 lbs and I would really love to get a motorcycle for my bday but I dont know what size as far as the weight and the CC's that I need. I was looking at Ninja's and I like the way they look but I havent sat on one yet but I dont know if I need a 250 or a 500 or whatever.

Thank you for you HELP!