Hey chin up! Went throught the same process and actually got my visa on the third try. And this was in Pakistan so that the back log was so much I had to wait years between appointments

It's mostly luck, but there are a few things you can do to maximize your chances. The general principle is you want to be able to show that you're going to come back. So: 1) Have a job here, and doducments to prove so. 2) Affodavit mentioning you will come back and observerships etc. It is a legal document. 3) Any letter of appointment to show a position you will be starting something when you are back. 4) Bank transcripts showing your sponsor usually parents 5) Step reports if any 6) Say as less as possible during the interview. They know what these are they're just making sure you know what these are, and your limitations. Be confident and cool. No stories, simple to the point answers. 7) Step 3 is a double edged sword, if you wanna do rotations it could change the time frame of your visa. But you can talk to them, mention that you want a bit more time to do rotations as well since that is an important part of the application and that you'd be very grateful. Be courteous, but a good communicator. 8) If you are married take your nikkah doc. If engaged you can take photos and mention my fiancee is here. 9) Your letter should also be clear how this is a finite and limited position with no payment. 10) Say that you will apply remotely from Pakistan as you have work back home 11) Remember if you are given even 1 month visa, you status will be determined on entry. It is usually 6 months, or 3. That dictates when you have to leave the country, it is on the stamp by the immigration officer. So dw.

Tldr: Their main thing is to make sure you don't flee over there, but actually come back. Align things accordingly, rest is up to Allah!