You've kept in contact with her so you are not magically reappearing to chill with her. Should be pretty easy.
Eh, you don't have much to worry about with this. You maintained contact with her.
Not sure where you're staying, but you could always invite her back to your car, hotel, apartment to "look at photos from study abroad" -- women love foreign sh*t. Or you could bring an interesting "item" from abroad such as a rock that they used to build an important monument, etc. It'll be your excuse to invite her over to look at it so she's alone.
Don't kiss her on the date when you're out. If you kiss her and then say let's go back to my place, it's pretty clear what's next. Wait.
When you get home:
1) While she's standing by a window, sitting down, or something touch her casually. see how she responds
2) Get her to the couch (if you haven't already), touch her thigh while talking/laughing (basically something more intimate)
3) Wait a bit, and then go for a kiss at the right moment.
4) Once your tongue is down her throat. I don't need to tell you what to do next..
Good luck!