I am still very new at BJJ but a few months into training whenever I was able to gain Mount, I didn't know what to do from there lol. Now I know a few more moves, but I am interested to know what you all do from Mount. 
Arm triangle is a good one you don't sacrifice position to get the finish
The first thing I do is to make sure I am in a good position. So many guys think they have to start working submissions right away and lose position. My goal is to get up into the armpits and establish some top pressure. From there, I start working cross chokes that set up the arm bar.
- Learn how to maintain position first, low mount, medium and high.
2. Focus on subs that don't risk position first. Arm triangles, ezequiel chokes, americana. Then work on armbars (which usually mean you lose position if you mess the armbar up).
3. Explore transition to technical mount, then explore technical mount. Follow steps 1,2 and 4 here.
4. Explore transitions to and from mount. Half guard to mount, guard passes to mount, back control to mount. Then mount to knee on belly, mount to back mount, mount to side control, etc...
Double attack. Choke or armbar. Armbar or choke. Choke or armbar. Armbar or choke. Ad infinitum.
Vogel is correct.
I can't emphasize enough that you need to be able to keep mount. That's way more important than going for the submissions. The more confident you become in knowing you can keep mount the easier it will be to open up for submissions because you are confident there isnleaa risk of losing the position and all your hard work in attaining the position goes down the drain 
Punch. Once you get good at balance, elbows.
Josh Vogel - 1. Learn how to maintain position first, low mount, medium and high.
2. Focus on subs that don't risk position first. Arm triangles, ezequiel chokes, americana. Then work on armbars (which usually mean you lose position if you mess the armbar up).
3. Explore transition to technical mount, then explore technical mount. Follow steps 1,2 and 4 here.
4. Explore transitions to and from mount. Half guard to mount, guard passes to mount, back control to mount. Then mount to knee on belly, mount to back mount, mount to side control, etc...
Very nice, thanks. This is very helpful. VU
SeniorWings -Josh Vogel - 1. Learn how to maintain position first, low mount, medium and high.
2. Focus on subs that don't risk position first. Arm triangles, ezequiel chokes, americana. Then work on armbars (which usually mean you lose position if you mess the armbar up).
3. Explore transition to technical mount, then explore technical mount. Follow steps 1,2 and 4 here.
4. Explore transitions to and from mount. Half guard to mount, guard passes to mount, back control to mount. Then mount to knee on belly, mount to back mount, mount to side control, etc...
Very nice, thanks. This is very helpful. VU
My pleasure, thanks!
MarsMan is spot on....too many people lose the position because they simply think once there they can maintain with weight. The most important step to a excellent mount is to be able to remain active while in the position which in turn sets up infinite submission opportunities.