If you are unlucky enough to get a split in your tyre casing, then this idea will ensure you get home.
Make up some of these free patches now, put some with the tool kit on your bike, if you have more than one bike then do it for all of them, any bikes that you miss are sure to be the ones that get a split tyre. In your re-cycling bin look out some of those plastic toothpaste tubes, some of them have a thin metal inner, or a plastic milk carton is equally good. Then cut them up into squares and oblongs, these will enable a repair that can get you home, just place one between the inner tube and inside of the split tyre. You will find that they prove to be very strong, and will allow you to inflate a split tyre to quite high pressure, enough to get you home.
Just make sure that you have a few in the repair kit on your bike(s).
How to adjust your derailleur gears
Use this link to learn how to adjust your derailleur gears