It can be helpful and atmospheric when roleplaying to perform physical actions that mimic what your character wants to do. Standing up to deliver a dramatic pre-battle speech to the troops, beating your chest and ululating when summoning the creatures of the jungle to your aid, or whipping around your replica bat'leth when fighting off hordes of hostile aliens.
Just remember that your dexterity score is probably about 5 points lower than your character's, and be careful.
Han: Luke! Boy, am I glad I found you!
Luke: Han... Must get to... Dagobah...
Han: Don't worry, kid. Your suffering out here is over now.
Luke: More wealth... than you can imagine....
Han: What? Wealth? I don't know, I can imagine quite a bit.
Luke: Must... find...
Han: I'll help you, kid. First, let's get you warmed up.
Han: I look around for firewood.
GM: Um. There's snow. And Luke. And his laser sword.
Han: Woohoo. Laser sword! I turn it on and wave it around. Like this! To warm the air up.
GM: Yooou...'d better roll.
C-3PO: Are you even proficient?
GM: You slice open the belly of your tauntaun.
R2-D2: The entrails say "no".