Inside pockets are essential components to any casual or formal jacket. Historically, the inside jacket pocket was crafted to deter pickpockets from the temptation of stealing. Men believed that having a "hidden" pocket would protect their valuables, such as cash and important documents. Making an inside pocket is an effortless process. Select the side of your jacket without a pocket and make it large enough to hold your checkbook, wallet or mobile phone.

Trace an outline of the pocket onto a piece of cardboard. Make the dimensions 3 inches wide by 4 inches deep. This dimension is wide enough to fit a passport or wallet, for example, and deep enough to keep a fragile phone safe from falling out. A 3-by-4-inch tracing will also account for the creation of pocket hems in later steps.

Cut out the cardboard tracing. Place the cardboard piece onto a flat piece of satin. Cut out the satin piece to the cardboard dimensions.

Create four hems to prevent the satin from unraveling. Fold one side of the satin over 1/4 inch. Sew the 1/4 inch edge into place. Repeat for the remaining three sides. You should now have a 2.5-by-3.5-inch satin piece with four clean edges.

Lay the jacket out onto a flat surface. Face the clean side of the pocket -- without exposed hems -- facing outward on the inside of the jacket. Center the pocket into place wherever you prefer it. Sew the right side of the pocket into the inner jacket lining. Pull the pocket taut and sew the bottom and left sides of the pocket -- leaving the top side open to place in and retrieve items.