Wool, despite being a thick material, can still become damaged or torn. Too much stress on the fabric, insect damage or worn spots can result in unsightly holes and tears. Luckily, like most other fabrics, wool can be repaired. You don't need to use any special method for repairing wool. It can be treated like other fabrics. As long as you have some basic mending experience and knowledge when it comes to clothing, this is a fairly straightforward process.
Thread the needle. Insert the end of the thread through the hole in the head of the needle.
Align both sides of the tear, whether on a seam or not, so they match the position they were in before the tear.
Complete a zigzag stitch through both sides of the tear. This is a stitch that involves no more than going back and forth between each side of the length of the tear.
Knot the end of the thread to secure the repair.
Cut off the excess thread with scissors.
Cut an iron-on patch to a size slightly larger than the area of the tear.
Lay the damaged area of the wool suit on an ironing board. Smooth the fabric with your hand to remove wrinkles. The patch needs to be applied to a completely flat area for the best bond and resulting appearance.
Place the patch on the surface of the wool suit.
Press an iron onto the surface of the patch and the suit. The heat will activate the adhesive on the back of the patch. The iron should be set to a wool setting or the setting recommended by the instructions that come with the patch.
Allow the patch to cool before wearing.