If you want to be the prepared gal, here are some ideas. For STIs, etc:
-have condoms in your handbag, don't rely on the guy to have them
-get yourself checked for STIs every 2-4 weeks (this is the average frequency that pornstars use and they actually have lower counts of STI transmittance than the normal populace)
-obviously, take the pill, or the coil, etc to minimise risk of pregnancy
As for meeting guys, two options:
Offline
Online
Online, you have a bazillion dating apps. As mentioned, a lot of guys on there are for the hit and run. Quite a lot of my female friends have an abundance of options through those apps, when it comes to casual sex. Simply get some good photos of yourself, write a little about you, upload it.... and wait for your phone to start breathing heavily.
Offline, you have your work, the cafe you pop into all the time, the street, the bus stop, the bus, the bus after that, etc. You can literally meet anyone, anywhere

The trick to enticing a masculine, male human being, is to simply catch and hold eye contact with him, give a small alluring smile (dont show teeth), and if you happen to be close to him, simply say "nice (insert some visible detail of his aesthetic). If he doesn't get the message and take the lead, then trust me, you would have bigger problems with him down the line due to his lack of social acuity.
Hope this helps
