Place the ball on the tee. Grab the club. Get a good, firm grip on the club. Position your feet apart and in line - where you want the ball to go. Bend your knees a bit. Focus on a particular point or spot on the ball. Slowly breathe in and out. Keep your left arm straight. Slowly bring the club back, not too far, 
keeping that left arm straight. Then as you come down, put pressure on your left leg and put some force into your swing. Then whack the ball!
Here's a vidoe to help your sweet success at golfing:
Note that Ivy lifted up her right foot and didn't keep her left arm straight - bad news. You must keep both feet on the ground and arms straight. Try again, and again, again, again, and again until you got it down. It's a good thing we aren't professional golfers but at least we had fun and (Ivy) looked pretty cute!