Roleplaying Tips.

Yup, this can be the most embarassing part but just remember it is optional. When an individual role plays, it is like they are acting as a character. This can be done verbally (for example you say "Bok the Barbarian shouts "SMASH" and slams his hammer on the goblins shoulder"), or physically where you actually act out the action. It can feel a bit uncomfortable doing all the physical actions but you can be as colourful as you like when it comes to verbal descriptions. Everyone's imagination begins to fire and combat just got that bit more interesting. You never know, you could get some more experience points from the Dungeon Master as a reward!
Be creative the way you speak to the Dungeon Master (when the Dungeon Master is acting like an NPC), if your character has a stutter, then do so! Does your character speak loudly? Quietly? A bit chaotic? Incoherent? Mumble to themselves?

Examples:

• Blue orbs of energy is released from his hands and slams into the skeleton (Wizard - Magic Missle)
• Raising his axe to the heavens he slashes at the harpy's wing (Fighter - Melee attack)
• Lightly grasping his necklace he closes his eyes to mumble a prayer, green light streams from his hand to the wound (Paladin - Cure Light Wounds)
• He clears his voice and sings of great battles past (Bard - Inspire)
• Drawing his bow out, he releases two arrows at once, towards the minotaur (Ranger - Double shot feat)
• Raising her hands to the sky she calls to the Gods, a bright light blinds the area (Cleric - Turn Undead)
• He clenches his fist and and looks down with his eyes closed, his head snaps up and charges into battle wih fury (Barbarian - Rage)
• He wraps his cloak around him before blending in with the night (Rogue - Hide)
• She dashes up to the edge and jumps like a spring (Any - Jump)
• She frantically wraps bandages around the wound (Any - Heal)
  
  So you may have a few ideas about how your character will act. It is best that you should say the action and then roll the dice. Bear in mind that you should keep the skill rolls, attacks and some spells open-ended (i.e. not implying success or failure) because you should say the action, roll the dice and the dungeon master will tell you if you have succeeded or not. Upon succeeding, you can then continue the sentence.