Baseball Bat: Tap it on your shoulder and then steady it on your foot.
Machete: Turn the Machete around and look at it in your hands, inspecting it and maybe brushing your hand across the blade.
CombatKnife: Flip it backwards and hold it, then take a few practice slashes at the air in front of you.
Sledgehammer: Hold it Horizontally with both hands and spin the sledgehammer, watching the head spin.
Flashlight: Tap the flashlight on your hand to a beat that cannot be heard.
Hookaroon: Roll it off of your right hand, catch it in the left, then roll it back, just continuously moving it around between your hands
This is just what I imagined myself doing if I were bored and had one of these in my hands. I tried to keep away from anything stupid or unnecessarily dangerous like flipping the knife between your fingers or throwing the sledgehammer into the air.