You should try self boosting or barrel flying. I have a link taking you to a video on how do it...
Self boosting is a form of jumping but going into unnaturally high distance (Not intended to be in the game). Set your FPS to 30 and Physically quality to low. Then; while you are trying to reach a very high platform, press "0" and try to jump as you would on a normal platform, while you are jumping you need to continuously left click your mouse and hold "x" to reach very high distance.
There is also barrel flying which is quite simple. Those explosives you see littered on the maps are the ones I am talking about. All you have to do is hold "c" which is kinetic module allowing the player to move certain objects. Just put the barrel under yourself and activate the kinetic module on the barrel and move your mouse but you have to do it carefully or else you can lose a ton of health or even death. Try using heavy battle suit when doing the barrel flying since it's really dangerous to do it on your first try.
Here is a video to make things more clear.
http://screencast-o-matic.com/watch/cD1eVDi69S