Wii Sports/Bowling

Bowling is fairly simple to pick up.

Controls
Use the D-Pad to aim left or right. Press to switch between moving left and right to facing left or right. When you are happy with your aim bring the Wii remote up to you then hold and swing back, then swing forward releasing  when the controller is facing down to release the ball.

Spin
Spin can be put on the ball by tilting the controller on or before release.

By using the directional buttons before swinging the wii-mote to bowl, you can move your character along the foul line. Pressing, then using the directional buttons can make your character aim their ball to the sides. Once again, experiment, and try the training exercises.

The sooner you let go of the button the more spin you will put on. For example if you wait for your mii to raise the arm upwards before releasing then you will throw the ball and not get much spin on. However if you release when your Mii's arm is near the ground then you will get a lot of spin on it.

Strike
A popular technique for getting a strike is to position your Mii so as to be 3/4 of the lane to the right (assuming you're right handed, reverse if you are left handed) and angle the path of your ball left so that it will strike the first pin. When you throw the ball make sure to release it a tad late so as to avoid too much spin and this should hopefully result in a strike. Vary said technique based on personal preference.

Unlock
Become a pro at the game then you will get a shiny bowling ball to play with.

Other
If you get your aim and throw correct then you can get your bowling ball into other players' lanes.

If you release the ball while your Mii is winding up (the ball is behind him/her), the ball will fly backwards and the spectator Miis will jump up and do a 360-degree spin.