I see a few issues with the premise of the question (spoilers ahead):
1- Kylo wasn't doing this - The first time the connection happens, Kylo questions Rey about it, thinking she's behind it somehow. He then mentions "the effort would kill you"; indeed, a similar use of the Force severely weakens Luke at the end of the film, so it makes sense that neither Kylo nor Rey would be behind this feat. Snoke claims he was behind it, which seems likely, given that he is much more powerful than Rey or Kylo. Later on, Rey and Kylo see each other again, but by then they've both experienced great personal/spiritual growth, and are also only a few miles away.
2- The timing wasn't perfect - Otherwise Kylo would've known to put a shirt on. Plus, the first time it happened, Luke was right there. Which leads me to my third point:
3- They didn't need to hide from Luke- As Rey trains with Luke, she realizes he has closed himself off from the Force. The first time she sees Kylo, she thinks Luke can see him too, but really he can only see the hole she shot through her hut. Only the last time Rey and Kylo meet, when they touch hands, does Luke see Kylo (because Luke has reconnected with the Force).
So, based on these three points, the Force projections aren't perfectly timed, and neither Rey nor Kylo are in charge of when they happen.