How do I figure out my measurements?

For Pants Hem- Measure the outseam of a well-fitting pair of pants by laying them flat and measuring from the top of the waistband down the desired length of the pants. 

For Dress Hem- Measure a dress laid flat from the neckline to the desired length.

For Sleeve Shortening- Measure from your shoulder down to your wrist while wearing a well-fitting top. This measurement tells us how much to shorten the sleeves.