first step is finding a place where to hold the part while painting. this is a very important step because you should find a way to hold the piece without covering any important area from paint.

th parts with sockets make this process much easier, just find a barbecue stick that fits snugly into the socket and use that as the handle while painting like this:

shake the bottle  well a few times before spraying. test spray the can upside down to make sure the nozzle isn't clogged up. keep the part and the can around 15cm in distance and spray in a diagonal motion around the part, spray in single bursts until you get a nice thin layer of paint on the piece. don't spray continuously or else the paint will pool on the edges and this could cover important details, you wouldn't want that. oh, and by the way you should always remember to wear gloves, painting over your your hand isn't nice at all.

[after applying the decals, battle damage, and weathering]

i overdid the weathering on this part, but it's for you to decide the intensity of the damage.

dry brushing  makes the whole process worth it.

don't cut to close to the decal, leave enough space for you to proceed to the next step.

now as long as the setter solvent is beneath the decal you are free to move the decal to where you wish it to be, just incase the solvent dries, add a bit more.

once the decal is in place, roll a q tip above the decal to release any leftover solvent beneath the decal.

same applies to the mr. mark softer solvent, apply the solvent on the corners of the decal. doing this melts the edges blending it with its surroundings. leave it to settle for awhile and roll another q tip to clean any excess solvent. 

even if the softer is applied the edges are still quite visible, so spraying a top coat or two can do the trick.