In Sikkim technical climbing experience is not necessary, since most of the trekking routs are between 1600 to 14,000 feet, but yes experience can be plus point. All the trekking and camping equipments are available for hire. Most travel agents and tourism department in Sikkim can provide the needed equipments. The most ideal time to go trekking in Sikkim is when the sun is shining and sky is clear, which is between February to May and October to December.

Trekking in Sikkim is wonderful experience, as trek routes pass through beautiful surroundings, lakes, hilltops, monasteries and colorful flora and fauna.  Yuksom is an ideal take-off point for trekking. This point is invariably used as a centre of climbing and trekking expeditions by the Himalayan Mountaineering Institute, Darjeeling. The trek to Bakhim is an unforgettable B experience. Dzongri at an altitude of 3,962 meters offers the visitor an excellent and unobstructed view of the Khangchendzonga Massif. It also provides a trekker with superb views of sunrise and sunset. 

Permits:

All foreigners need to obtain permits to trek on most routes, local travel agents can easily provide your permits from Sikkim tourism office, or you can directly get the permits Delhi, Kolkatta and Siliguri Sikkim tourism offices.
Obtaining Inner Line Permit | Restricted Area Permit (RAP)

There are numerous hiking and trekking routs in Sikkim, Some are not open to foreigners and some routes are not even explored.  Here are some popular treks offered by local travel agencies:

1. Yuksom - Tshoka - Dzongri - > Thangshing - > Samiti -> Goechala Pass
2. Uttaray - Dhor - Meghu - Garakhet -  Pangdim - Dzongri - Thangshing - Lamune – Goechala - Thangshing - Tshoka - Yuksum
3. Pelling - Kechoparli Lake - Yuksom - Tashiding