Method 1 (Completion)
Arguably the trickiest portion of this level to tackle is at the very beginning, right at the top. If you haven't tried it already, the singular mine at the top of the map prevents you from taking the most direct route, forcing you to tackle the mini floorguard puzzle in the tunnel.
The tunnel has 3 access points. First, enter from the leftmost one, closest to the starting point. This will trigger the floorguard to move to the left. Immediately after the trigger, jump out of the tunnel to prevent an early death, and make your way to the middle access point. Meanwhile, take care to avoid the lone seeker drone patrolling the area.
Now, enter the tunnel via the middle entrance. The floorguard, which should be at the left of the tunnel due to your previous trigger, will now move right. Jump straight up and let it pass, and fall right back down into the tunnel from the same entrance. Now the floorguard, which should have completed its journey to the right, will start chasing you towards the left again. Now for the final stretch: jump straight up again and let it pass to the right, fall back down, and race towards the rightmost exit, also your gateway to freedom. Still mindful of the seeker drone, exit the tunnel and grab the exit switch while avoiding the lone gauss turret, which shouldn't pose too much of the problem. Congrats! You've done away with the trickiest portion of this level.
Now we move on to the second section of the map, as you drop down the right triggering the trapdoor which prevents re-entry to the first section, not like you want to go back anyway. The chamber containing the laser drone should be locked, so just bypass it, and proceed towards the launchpad. There is no opposition here, unless you were a little on the slow side and allowed that lone seeker drone to move on. Trigger the launchpad, and basically follow the green path nabbing the switch while avoiding the laser drone (just move quickly and the laser won't hit you). Drop, move on to the final area, avoid the floorguard poised to destroy all you've worked for, and move through the little hole you've created and to the exit.
If you want to be done quickly, and avoid having to deal with zap drones in the second part, do this. As soon as the level starts, jump onto the platform on the right, and up onto the little block just before the floorguard puzzle. Wait there for the zap drone to see you, and then jump down into the floorguard puzzle. Get past it as described above, quickly get the switch, and drop through the trapdoor, locking the zap drones in the first part. Finish it as explained above. Note: You cannot get all gold using this method.
Method 3 (Speed)
For speed, it is possible to jump over the mine at the start. All it takes is a lot of timing. See speed runs on NReality for details