I had someone message me asking about these positions and I didn’t see any other tutorials about the subject so here are some basics of how they operate. This doesn’t go totally in depth on each one but a basic understand of each ones role.
Ok so let’s start with departure a lot of the commands are used in all three stations basically they tower should hand off to departure just after take off. They will either ask for radar vectors, flight following or VFR flight. If they don’t say their intentions just ask for them so you know where they are going and what they will be doing. Radar vectors this means they want you to guide them to their destination. Give altitude as well as heading until they are 30 miles or so from the airport then hand them off to center. If they ask for flight following that means they have a flight plan they wish to follow this is for VFR traffic. if they don’t have a flight plan or are not a VFR aircraft don’t let them proceed with this request and give vectors and altitude. If they do have a flight plan let them proceed on course and don’t bother them again unless they request something or they need to turn or change altitude for other aircraft. VFR flight this is Visual flight rules they must stay under 10,000 ft don’t send any other messages unless absolutely necessary. Also hand off planes 30-40 nm away from your controlled airport.
Center controls traffic from SRF to FL600 same commands are to be used. They may also request an ILS approach from center this means they will enter straight in at a 30 drug angle so vector them to where that can happen and handoff to approach when decending and within 30 miles of the destination airport.
Approach same commands as center ILS approaches you want to vector them to a straight in at a 30 drug angle and get them to decend to 3000 ft AGL right as they enter the red triangle.
NOTE always consult the published departure and approach plates/charts for the airport your controlling and use they way points to help you guide people in. This tutorial really helped me know when to have people start decent and at what speeds.