The first ability lets you roll a six-sided die and put that result on Socketed Sprocketer. This basically saves that result for later use. Say you roll a 5. Put the die on Socketed Sprocketer with the 5 face up. Later in the game, when you roll another die, you can choose to use the 5 instead of the result. (You'll see the result before having to decide.) If you have a 6 installed on Socketed Sprocket, you can just uninstall it to draw a card. If you do this, the 6 is gone and can't be used to replace a future die roll.