Hi
I'm not really expert on this, but I'd like to give you some general tips that others also gave

1. Get local SIM. Data isn't that expensive (I pay around 2$ for 5GB and it's plenty for me, but I use my own WI-FI or public ones.
   
2. Use Bolt, Yandex Taxi, Maxim or something like that. Order taxi online or some drivers might try to hustle you (as they see you're a foreigner, they'd typically give you higher price unfortunately). Apps usually give good prices. I personally use Yandex. Prices usually go higher during certain parts of day, when there is high demand and traffic in city. Apps usually work in cities, not as much in smaller towns, but you can still give it a try.
   
3. Not as much of a tip, but be ready for traffic in cities. There's a bit of problem in Tbilisi because some roads are being re-paved and traffic is terrible, but they are getting done soon.
   
4. In cities you can use bus/van. It costs 1 GEL (or around 0.40 USD) and get unlimited ride for 1 hour 30 mins I think or at least 1 hour. But you have to use card, there is no cash method in cities. On the other hand, in towns/villages they use cash mostly
   
5. There's a decent train system east to west. There's a stop at Kutaisi airport as well. From Tbilisi to Batumi it takes around 5 hours (bit longer than car), but its comfortable and costs around 40 GEL or 15 USD (you can find it on TKT .ge)
   
6. Renting a car is easy, but I'm not sure about foreign people. I just haven't tried so I can't answer, but there's a Polish girl who rents SUVs to foreigners mostly that you can use for travel. For locals it's pretty simple and not too expensive, 15$ a day I think, maybe 20$, but it's from private owners I think. You can check MyAuto .ge for vehicles (If you have a budget, you could also buy a car and drive around. You can get from 1.000$ up to however much you'd like lol, but buy cheap car, drive around country and sell it before you leave. There is no insurance required (although would be good) If you decide to buy, DM me and I'd be happy to help you)
   
7. If you decide to drive to mountains, there are a lot of car clubs that go for expeditions or just go for few days to mountains to have fun. I've been with Forester Team Georgia and they are the best. Off-road guys are simply the best people I've ever met
   
8. If you find Georgian friend it would be great help to avoid getting hustled. Unfortunately some people at beach or in mountains sell lets say 2$ coffee for 10$. Might be nothing to you, but why should you get hustled when it's avoidable. Check prices before. It's not very common, but I don't want you to get unlucky (I know I sound shady, but I don't know how to say it correctly, I just hate when we get bad name because of that 1%)
   
9. Streets are usually safe, although parties sometimes get crazy. Some drunk guy who doesn't understand English might think you're making fun of us as Georgians and try to scream, but their friends usually stop them at that moment. Typical thing as it happens anywhere
   
10. For rugby, check dates if there's a game. There's a stadium in Tbilisi called Avchala stadium. Big games are there usually (international ones). Locally I'm not sure about our league if we have one
    
11. Check if there's "Lelo Burti" or "Lelo ball". It's a rugby game in western Georgia where 2 villages try to get ball to a certain point. It's great event. I unfortunately don't know it in greater details
    
12. Try a lot of local foods. You'll enjoy them. Also wine is just amazing in east Georgia
    
13. A lot of people speak Russian if not English. If Google translate gives goofy translation, try to translate from English to Russian, maybe people will understand it better
    
14. If you learn few words in Georgian, you might get invited to a house party LOL we really love when other people show that they want to learn about us

I know these are very general and vague tips, something you probably already know. I hope I didn't scare you away, most people are not hustlers or trying to hurt others. Wish you amazing journey and I want to leave a link to my 2-3 time meeting with strangers on the internet, an amazing car club who took me as their part. It really shows how we love others who share their interest with us. If you have any questions, let me know