I use to have to rummage around for ages, trying to find things in my bag but now I'm super organized and can grab whatever I need straight away.
Cut yourself a large rectangle of oilcloth measuring 130 cm wide by 35 cm high. You can alter the dimensions depending upon the size of your bag and how much you want to fit in it.
Fold up the bottom edge of the fabric and pin in place. Sew this down, removing the pins as you go.
Fold down the top edge of the fabric by 10 cm and pin in place.
Sew along the edge where it meets the middle of the fabric.
Lay the strip of fabric down and then group together everything you want to store.
Place each group along the fabric and fold up the bottom edge by 10cm. Pin where you would like each of the pockets to go.
Remove all your stuff and sew your pockets in place.
If you want to make a loop for your keys, cut a thin rectangle of oil cloth.
Fold in half and sew along the open edge.
Stitch this in a loop to the organizer. You can attach a keyring on to this and clip your keys on to this.
Put everything in it's place.
Put the organizer inside your bag and you're ready to go.