Firstly, it is prudent to identify exactly what a fade and a draw are.
The fade is a golf shot for a right-handed golfer that starts left of the intended target and curves slightly in the air to finish on the intended target line.
A draw for a right handed golfer is a shot that starts to the right of the intended target line move slightly from right to the left in the air and finishes on the intended target line.
Therefore draws and fades are normally considered to be good shots as they both finish of the intended target line. They should not be confused with slices and hooks which by definition are poor results that finished away from the intended target line.
A golf ball curves in the air due to the spin that is imparted on it at impact. Every ball that is hit with a lofted club face will have backspin on it, but sometimes this backspin will be tilted off its vertical axis. This is sometimes described as side spin as the ball will be seen to spin to one side in the air. The backspin will be tilted if the path of the club and the face of the club are not heading in exactly the same direction at the point of impact.
For example, if the swing path is heading to the left of the target line and the club face is open to the path, the ball will spin with what could be described as left to right side spin which would make the ball move from left to right in the air. The ball may not actually have side spin on it. It would in fact be the backspin that would be tilted in order to make the ball move in the air.
Likewise, a ball that is to draw will be hit with a swing path that is from an in to out direction. Where the club is swinging to the right of the intended target, the club face will be aiming less to the right than the swing path. The club face could be described as closed to the path. This creates a draw spin and the ball will move from right to left in the air.
If a golfer can get the right balance between the swing path and the club face relationship, they can learn to create the right amount of curve in flight to produce consistent draws and fades without slipping into the bad shots which are slices and hooks.