Mark the center front of the left leg.  Mark the point that's halfway between your first mark and the side seam.  That second mark should be the center of your design.  The bottom of the design should be 1/4 to 1/2 inch above the hem stitching on the lower edge of the shorts.   

The design should be on the left leg at the crotch level, and centered between the side seam and the inseam.  

Bottom of monogram should be 1/4 inch above the top of the buttonhole.  

Monograms should be 1/4 inch to 3/8 inch high.  The collar may need to be removed and replaced.  

Halfway between the center neck front and the left shoulder seam.  The bottom of the design should be 1/2 to 3/4 inch above the edge.  

Should be 1/4 to 1 inch tall, depending on size of collar.  Follow the direction of the edge, don't try to turn at an angle so it's straight when you're looking at it.  

Top of monogram or name should be 1/4" to 1/2" from the top edge of the pocket, and centered between the left and right edges of the pocket. 

Bottom of design should be 1 1/2 inch above stitching for lower shirt hem.  Center of design should be 2/3rds of the way from the center front to the outside left edge (approximately 7 inches from center).  

Center the design from left to right.

Bottom of design shouldn't go below the armpit, but on a very large design, it should be high enough so it won't be hidden if shirt is tucked in.    

Large irregularly placed designs usually follow a diagonal or large gentle S curve or C curve.  Frequently, the design will start at the right shoulder, come across the bodice, ending at the left waist, or curving at center of the bodice and ending at the left waist.  The design may also curve at the waist, and come back across the top of the pants or skirt.  Embroidery sewn on one side, placed off center, and carried down the leg, creates a vertical line.  

The embroidery should be placed so it enhances the shape of the garment, flatters the wearer, and doesn't get in the way of movement.    

Center the design from left to right.  
Center top to bottom with the middle of the armholes, from shoulder seam to armpit.  Design should be placed lower on sweatshirts with hoods.

Draw line straight down from where shoulder seam meets collar seam.
Find center of armholes, from armpit to shoulder, and draw line straight across. If you place this line too low, the design may go across a woman's breast area.
As an alternative, you can draw a horizontal line at the level of the second button or snap.
On a V-neck shirt, you can draw a horizontal line even with the bottom of the V.

If you're only putting embroidery on one side, then the name and/or logo should go on the left chest position. If you're putting the person's name and logo on two sides, the name should go on the right, and the logo should go on the left. Rationale: When you shake hands, your eye naturally falls to the other person's right shoulder/chest area, so if their name is on the right, you're more likely to remember it.

Center design over pocket for your left to right measurement. Bottom of design should be 1/4 inch above pocket.

If the pocket is crooked, then line the design up with the pocket, and chances are that nobody will even notice. Otherwise, it will look as if you put your design on crooked.
The design or lettering should never be wider than the pocket, which is usually about 4 inches.

Center the design from left to right.

Bottom of monogram should be 5 inches above hem or 2-3 inches above border.  Place on opposite end from the label.

Bottom of monogram should be 4 inches above hem or 1-2 inches above border.  Place on opposite end from the label. 

Bottom of monogram should be 2 inches above hem or 1 to 1 1/2 inches above border.  Place on opposite end from the label. 

Bottom of monogram should be 1 1/2 inches above hem or 1 inch above border.  Place on opposite end from the label.

If there is no border, monogram may be placed in corner at a 45 degree angle.

6 inches above hem, or 3-4 inches above border.

Approximately waist level, on the right side of the coat lining, 3 inches from where the lining is attached to the outer material, near the front edge.  

Draw line straight down from where shoulder seam meets collar seam.  
Find center of armholes, from armpit to shoulder, and draw line straight across.
As an alternative, you can draw a horizontal line at the level of the second button or snap.
Center of design should go where lines intersect.  

Center design from left to right.
Top of design should be 2-3 inches below bottom of collar, or 4-5 inches down from base of neck.  

Draw line straight down from where shoulder seam meets collar seam.  
Find center of armholes, from armpit to shoulder, and draw line straight across.
As an alternative, you can draw a horizontal line at the level of the second button or snap.