Here are some random tricks and tips that have proved useful during my builds.
Tighten Loose Joints with Super Glue
An inevitability with gunpla are loose joints. Be it from age, poor engineering, or a lack of polycaps (I'm looking at you, F91 era kits). To help tighten things up just pull the piece out, apply a little bit of glue to one part of the connection, and let dry. DO NOT GLUE THE PIECES TOGETHER! Once the glue has dried you'll find a much tighter fit on the joint. If it's not yet tight enough apply more coatings as desired. A word of warning, too much glue can make for a very tight joint. Sometimes it can be difficult to fit the connection if you've applied too much glue.
Mask Thruster with Putty
Did you pick up poster putty for painting? If so, you can use a ball of putty to mask the inside of a thruster while painting the outside. Paint the inside of a thruster your desired color. After it's dried ball up some putty and place it in the thruster to the edge where you want a color barrier (ie the end of the thruster). Then paint the thruster as a whole, removing the putty once complete. Pictures to come!
Spray Can Storage
Those who use spray cans know that they can take up a lot of space. Between cans leftover from other projects, or ones I pick up because the color might be useful somewhere down the line, storage can be a pain in the butt. Like many you've probably ordered a kit online and have been awarded a nice cardboard box with any number of applications. With a bit of tape and a box cutter you can double your storage capacity. Simply tape the box closed (with nothing inside, obviously) and cut down the middle. You'll have to tape the other half eventually and doing so in advance provides stability during the chop. Not only do you now have two boxes but their lower height makes it easier to identify and sort through your supplies. Since most cans are of a uniform height they're stackable too!
Have any other nifty tricks or tips I may have missed or don't know about? Let me know!