As the golf season gets in full swing (no pun intended..) it is important to start with sound fundamentals. Your grip should be at the top of that list to help develop consistency and solid ball striking.
Lay the club diagonally across the fingers and palm of the left hand so the handle runs from the top joint of your forefinger across the middle of your heel pad. After closing your hand over the club you should be able to see atleast two knuckles of the left hand with your left thumb resting down the right side of the grip. The V formed by the thumb and forefinger of the left hand will point just inside your right shoulder.
In positioning the right hand on the club your fingers should be underneath the handle, then wrap the palm of your right hand over your left thumb. After closing the right hand your right thumb will rest lightly against the left side of the grip with the V formed by your right thumb and forefinger pointing just inside your right shoulder.
A ten-finger grip is often well suited for juniors and beginners because having the entire right hand on the handle promotes more hand action. As a players' priority moves from distance to accuracy they would probably benefit from either an overlapping or interlocking grip.
In regards to grip pressure use equal pressure with your fingers and hands holding the club firmly, but not the point of your arms being rigid. On a scale if holding the club as light as possible was a 1 and as tight as possible was a 10 I would start at a 5 or 6. Occassionally you will vary your grip pressure depending on the shot your trying to hit. To keep the ball low as when hitting into a headwind or trying to hit a punch shot you'll need a firmer grip. If you're trying to hit a high, soft lob shot to the green you'll want to hold the club much lighter.
If you've been holding the club differently than what I have described this new position will probably feel strange at first. Keep with it and through practice not only will it become more comfortable, but you'll hit straighter and more solid shots. I can't think of a better way to start off the golf season.