It's very hard work, and requires a lot trust, faith and firm boundaries. Same as any relationship really.

Talking 24/7 is about the quickest way to cause problems though. Cos if one of you can't for any reason, like work, life family etc. The other can very quickly become insecure assuming the worst.
You will also inevitably run out of stuff to talk about if you just pour it all out at the beginning.
It also makes for a lack of boundaries, being able to just contact your gf/bf anytime you like and get a response often leads,to unrealistic expectations with regards to each other's time.
I would say much like a normal relationship.
Say good morning. Chat in the evening, agree a reasonable amount of time for this, 2hrs is an example.

Then on weekends do something like watch movies together, or show each other around your local sights. I know it might seem a bit odd but it keeps things interesting.

Can it work? From experience I can say yes.I met my ex while at college, we then had a 9 month ldr which became a 10 year real time relationship.
(This relationship did end, but some just do, )
After a six year break, My current relationship started online, we have known each other two years finally started visiting each other 6months ago. And all is well.

I really hope it works out for you and your girl.Take it easy and set those ground rules.