The easiest and best way to properly carbonate your beer is to exercise a little patience and to equip yourself with the proper tools. In the case of carbonation, a gas table (see carbonation table below) is a pretty important tool.
With table in hand, you can select your desired carbonation level at the temperature your beer is being stored. Ideally you should carbonate your beer at the same temperature you will use for serving. Once you know the desired level of carbonation and the beer temperature use the gas table to determine the required gas pressure. This pressure is what the regulator on your tank will be adjusted to.
Once you have your gas plan, attach your keg to the carbon dioxide tank adjusted to the pressure dictated by your gas table and wait. A batch of homebrew is small and the headspace pressure will equilibrate with the beer in about 3 days. The only thing you can do to speed this method up is to periodically shake the keg. Some people want to bubble the gas through the dip tube in the keg, but this really does not speed things up much because the gas bubbles are too large and zip through the beer before much gas diffuses into solution. It also causes foaming. Take my advice and just hang tight! You can periodically shake the keg to speed things up, but whatever you do, avoid the temptation of cranking the regulator higher than what your gas table states and shaking the keg.