Bowling is fairly simple to pick up. Hold B, and raise the remote as shown on screen. Keep B held, swing your arm back (as shown on screen), then swing forward, and release B when you want to let go of the ball. Spin can be put on the ball by tilting the controller on release. By using the directional buttons, you can change where the ball will go. Press A, then use the directional buttons to rotate the direction. Once again, experiment, and try the training exercises.
The sooner you let go of the B button the more spin you will put on. For example if you wait for your mii to raise the arm upwards before releasing B then you will throw the ball and not get much spin on. However if you release B when your Mii's arm is near the ground then you will get a lot of spin on it.
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. It should be noted that an early drop may be equally effective. One, albeit cheap, trick to get an almost perfectly straight throw is to keep your arm held back until you have already ran up to the line. Then swing, preferably quite high. This will lob, or "pop" the ball, while still causing it to maintain a good amount of speed. If done right, a perfect game is easily attainable. However, because of the aforementioned cheapness of the move, and because it is not truly possible in real life, people should refrain from using this in a multiplayer match, in the interest of fairness.
The game can run within a playing session for a while without the DVD being inserted.