There's a great book covering exactly this called the E-Myth. Basically the myth is that all people who start small businesses are Entrepreneurs.

The truth is that most are technicians who are really good at their craft and know that they could make more money and be more effective if they were in charge.

The result is that most struggle with the transition between technician and manager because they are completely different skill sets. Most former technicians struggle to give up technical control and end up micro-managing and not realising that they can't do two jobs at once (or many more).

The advice is to plan a business by allocating all the roles considering expansion. Whilst you may be the technician & the consultant & the accountant & do the payroll & the hiring & the marketing & be the CEO all at once to begin with, ultimately you need to give up all of these roles as you hire new people.