The Pang Mapha district around Soppong is home to several hilltribe communities — primarily Shan (the dominant lowland group), Lisu, and smaller numbers of other groups who have settled in the hills. Walking between villages through the jungle and bamboo forest is one of the most pleasant ways to spend a day or two based in Soppong, and it's still possible to do this on relatively quiet trails without the heavily touristic atmosphere of the Mae Hong Son and Chiang Rai areas.
Market day in Soppong is Tuesday, when hilltribe people come down from the surrounding villages to trade, and you can see traditional clothing and handicrafts. Guides for village treks are available through the guesthouses — particularly the Soppong River Inn, which has run responsible tourism operations in the area for years. It's worth choosing a guide who has genuine relationships with the communities visited, rather than one who treats the villages as a photo opportunity.