Re: Where's the balance between no-contact and being fun and interesting?
The idea behind no contact is that it makes you more interesting, the idea that you are doing other things rather than waiting on her beck and call. Now she hasn't contacted you since shes been back? and you haven't made any attempt at contact with her either? If this is the case you need to make contact to let her know you're still interested, something like.. "So I heard you're back from (trip), How was it? Anything interesting happen? etc... After she replies make conversation and say something like "So I've been looking forward to seeing you again, Lets go (insert activity) This weekend."
Now if what has happened is you've contacted her, once, or possibly multiple times (which seems to be the biggest mistake guys make when they don't get an initial reply) then you're going to want to stop contacting her and wait. When, or should I say if she replies, don't reply right away like you've been waiting for her the whole time, wait a little. Hours to a day is a good time frame to go by. From there let her know you were otherwise occupied with something interesting and couldn't get back to her right away, and go from there.
As a very important side note, Many guys get the impression that texting her multiple times is ok. It's not, You send one text, at the most two and make them at least a week apart, or you'll seem like you're desperate.
React according to whichever above scenario applies to you, if neither of them do give me a more in depth explanation and we'll go from there. Good luck.
"Act like you're interested, not like you care."