Which style of grip that you use is largely a matter of choice based upon the size and natural strength of your hands. As a guide, use the overlapping method if you have large and or powerful pair of hands; the interlocking method if your hands are normal and not unduly strong.
As an example I use a ML glove and have played with the overlapping grip. Too often I found that with this grip the heel of the right hand opened during the swing. At first it did not alarm me, and I still managed the shot. However, as the heel of the right hand opened the right hand lost some of its grip and attendant troubles followed at the top of the swing. Changing to the interlocking method improved the situation straight away. The interlocking grip had the effect of tying the two hands together without causing either hand to open.
One achieves the interlocking grip simply by taking the normal grip with the left hand except that the forefinger is inserted between the little finger and forth finger of the right hand. The tip of it will rest over the back of the knuckle of the little finger of the right hand.
Note. Many of the top golfers using the overlapping grip do not have the little finger riding piggy-back, but hook the little finger around the knuckle of the left index finger. Making this modification is an improvement to the standard overlapping grip as it also, does not allow the heel of the right hand to open and holds it in during the swing. People with large hands do not have this problem when using the standard overlapping grip.