Approached this girl, took her number (she seemed indifferent at the time), invited her to a date, we had fun together visiting some places (she's a kind of silent personality, and I'm not good at reading emotions yet, so I can't be sure she had fun, but she said she did). Kissed and hugged in the end.

Invited her to another date. Again, had fun bowling and doing some other activities. More hugs and kisses, some initiated by her.

(Both times there was no possibility to invite her home, unfortunately)

Now, both times I called her like in 2 days (after I approached her, and after first date). So basically we had contact every 2 or 3 days (meet - phone - meet...). This time, I'm going to have no free time for over a week (I'm really busy). So there's going to be at least 11 days between our last date and the next time I can meet her.

So, is it better to call her somewhere in the middle of this period, maybe talk a bit, and schedule a date that will happen about a week ahead? Or should I just disappear for over a week (meaning, only respond if she calls), and then call her several days before I'm finally free to meet her and just ask her out? (I don't think explaining I was busy with this and that is a good idea, right?)

I'm personally not into this "playing with amount of days between your calls/dates to make her miss you more" thing, but judging by my past bluepill behavior, where I'd always chat over the phone when I couldn't meet a girl, it's not always productive (since you're entering a friend's frame and you look needy and you look like you're missing her). At the same time, I don't know if disappearing like that is okay. I wasn't dating for like 8 years (pointless bluepill LTR turned into pointless marriage) so I have completely forgot how it all works at the start. Maybe if I don't call her for some time she will just think I haven't enjoyed our second date or w/e and decide to forget about me? IDK.