Like in the previous part, I'd like to remind you, that I'm just sharing my own experience and expressing the personal opinion. No more than that.
Making a vacancy card
One of the most important criteria of your search success is the right choice of HR platform. Since we are working with IT segment, I'd like to recommend the Habr Career.
For an extra traffic source you can use Head Hunter, LinkedIn (blocked in RF) and various telegram channels. For example: a good channel to find java developers, this will help to find mobile developers, or you can use your personal sources, if you have them.