Hi. Greetings. Really not aware of any successful home remedy.. But you could try the following.
1. Firstly stop smoking... Else no treatment will work
2. Apply a up lip balm with sunscreen or atleast Vaseline two to the times daily
3. Mild peeling and lightening agent cream prescribed after due evaluation by dermatologist
4. Medicinal Peel therapy for lips may be helpful. Discuss with your dermatologist
5. Trial of laser if nothing else helps.
Let me know if u need any further assistance. Warm regards, Dr Govind Suresh Mittal, Excel Care hospital, Bangalore