If you find lumps in a can of paint that you need, you can "push" them out. Cut out a circle from a piece of wire screen slightly smaller than the can's inside circumference. Put the screen circle on the surface of the paint. With a little help it will sink to the bottom of the can, taking the lumps with it. Another way to salvage lumpy paint is to strain it through an old nylon stocking.
When you process wood in your shop, it is helpful to make notations on boards so you remember which have been cut to length or run through equipment like planers or jointers. Instead of using pencils for the notes, use chalk. Chalk lets you mark the wood without marring it so you can be more liberal with your notations. An inexpensive children’s sidewalk chalk set will provide several colors so that you can color-code your marking system.