Remove the bag and place it on a prepared backing fabric.
Circle the bag to the bottom of its lining was for 3-5 inches longer than the bag, and laterally on each side is wider by 2 cm. All this is necessary to ensure that after washing the bags, it could be possible to stretch hands and stuff packs or dry with towels to shape and to prevent deformation when drying.
Cut the lining symmetrical. If your lining provided pockets, then you need to cut two more pockets.
Treat the pocket edges with serging or zigzag stitching. To the side that is longer, you need to put a rubber band and stretching it the entire length of the pocket, neat stitch. Then tuck the elastic fabric pocket and stitch again.
Pin the pockets to the lining and sew them.
Fold the details of the lining facing toward each other and prostrochite them. Don't forget, however, to leave the upper part of the strip nepostroennye.
Insert the finished lining into the bag and pin around the perimeter, turning the allowances to 1 cm and Then manually sew the lining to the bag invisible stitches.
To hide an ugly seam on top of the lining you can sew a decorative ribbon or a loose braid, lace. You can not do this if the seam you turned invisible and neat, but, realistically, it will be even better. The lining pockets can be sewn and even a zipper for convenience, but each of you has their own preferences and wishes. The important thing is that now your bag has a new lining and do not have a problem finding the keys or the little things that fell through the hole in the old lining.