Do not store the jacket in direct sunlight for long periods. If the leather becomes wet, allow it to dry naturally for at least a day before you use it again. Also, you should never dry leather using artificial heat, such as a heater or hair dryer.
For a deep clean use saddle soap or dilute baby shampoo sparingly on any stains, but always patch test anything new on an area that cannot be seen.
To keep the jacket supple and in tiptop condition, use a wax dressing and apply every 12 months to keep the leather moisturised.
Leather Works Wax Dressing: Using a soft cloth apply a small amount of wax treatment (the wax is clean to use and practically odourless), apply sparingly, do not apply to the sections of fur or cloth (linings). Hang the treated item at a warm room temperature for a couple of hours. (Never use direct artificial heat or in direct sunlight.) Buff gently with a lint free cloth to gently remove excess. Leather Works Wax Dressing is available here.