Holding the mouse correctly will help with your comfort and accuracy. Your pointer finger should rest on the "Left Click Button" with your middle finger on the "Right Click Button". Your pointer finger will become the dominate on and will occasionally switch over to "the scroll wheel" to make for easier navigation and browsing. Practice positioning your hand to match the image to the left. Check your hand posture with the images below. This will help prevent wrist aches and pains.
A Mouse Uses a "USB" port to plug in and connect to the computer. The illustration below is a close up of what that looks like. Do you see that there is a plastic white piece covering half the USB port's entrance? That is normal! If you look at the end of your mouse's USB plug in, you will see the same thing!
*Tip: If you are noticing that your mouse is being stubborn and won't plug in, chances are you are pushing those white plastic pieces together! Try flipping the mouse USB port and try again. The plastic pieces slide under one another so that the cord is in there securely when you insert it.