How to talk to a possible straight girl on Facebook?

[Danielle]

Me and this girl have had a few FB convo's on statuses and stuff and we'll comment on each others statuses and pics every so often... I've thrown slight hints in the past and I get a feeling she might be into girls secretly or atleast me... I think she's thrown hints also but I didnt want to jump to conclusions...but I'm not positive and she doesn't know that I go both ways... I'm interested in her so what are some ways I could figure out if she's into me or bi should I keep flirting or strike up a convo in a message and how would i strike up this convo? im so lost lol