The first thing you want to remember is to type "Shepherd" on the opening screen (where you have the options to Read the Directions or Play the Game). If the screen automatically takes you to the field, then you spelled it right and your points will be doubled after each round. If you remain on the same screen, either close out of window and re-open it, or refresh (F5 on your keyboard), then try again. S-h-e-p-h-e-r-d.
The game seems best if your screen resolution is set to 800 x 600- where the screen size is smaller and everything looks larger. This way you can bowl more accurately (I, personally got my avatar with the 1024 x 786).
When the screen opens, it should look like the picture below. If all is set, continue. You will be the first to bowl. I suggest placing your cursor over the jack and slowly dragging it to the cybunny. Try to keep a steady hand. Once you reach the cybunny, keep your mouse on the ball.
Very gently hold down the left mouse button and drag backwards. I suggest bringing the line to the back of the cybunny's head and letting go. This will provide the bowl to glide smoothly across the field and either just touch the jack, or land a bit away from it. Repeat this process but try experimenting by putting your cursor (before you toss the bowl) right ontop or right below the jack then following my tips.
Try bumping your own bowls to move them closer to the jack. Be careful, though, if you hit your opponents, you could cause them to win. You can also try- if you're desperate- to knock your opponents bowl all the way off the screen, or far away from the jack. I suggest only doing this if you have about two bowls very close to jack and your opponent's bowls keep getting nearer. This is a good plan to use on round 3 for the more difficult opponents. Also pay heed to their position and the position of the jack. You do not want the Round 3'ers to gain extra points because you knocked the jack out of bounds.
I would stay away from aiming the line towards a wall and letting it shoot up the opposite way. Most of the time it will roll off the side of the screen. On the 3+ rounds, you will notice that there are Zeenana Peels and Holes. Avoid all of them. You will notice that your bowl may run over the side of the holes and it will not go in. Take advantage of that and attempt to get near the jack, but avoid allowing your bowl to slide completely into it. Try avoiding Zeenana Peels completely, they cause your bowl to roll in a random direction (away from you).
If your hand is sore while you're playing, don't be afraid to stop and take a break. The game isn't timed so you have as long as you want to plan your next move. A sore hand often causes irritability and that just builds as you get to Round five. At the quarter-finals you may find it helpful to get away from the computer and grab something to eat or anything else that may calm you down. The next three opponents are tough and use tricky moves. I wouldn't try matching the diagnol move unless you're trained.