When trekking in the jungle, we recommend wearing good hiking or sports shoes and long pants. This will protect you against stinging and poisonous plants (up to 2 % of plants in rainforests) as well as insects of all kinds, beetles and certain arthropods.
Here is our recommended equipment list for a 2 or 3 day trek in Northern Thailand:

1 - a small backpack ;

2 - a pair of walking shoes or good sports shoes (avoid smooth soles);

3 - sturdy pants (military fatigues are best!);

4 - 2 or 3 T-shirts or shirts (as for pants, "natural" colors - black, green, brown, gray, camouflage - are preferable to bright colors if you want to see animals (fluorescent pinks, reds or yellows are to be avoided!);

5 - 2 or 3 changes of underwear (briefs, panties) ;

6 - 2 or 3 pairs of socks (it's important to always have a spare pair of dry socks, as feet get wet in the jungle!) ;

7 – Un maillot de bain (les chutes d’eau sont fréquentes en jungle et il est possible de s’y baigner) ;

8 – Une serviette de toilette ;

9 – Une trousse contenant les affaires de toilette (brosse à dent, dentifrice, savon, rasoir, etc.) ;

10 - a hat (bob or cap) ;

11 - An anti-mosquito spray ;

12 - a headlamp or flashlight (some tribal villages have no electricity!) ;

13 - a poncho or K-way (especially in the rainy season between late July and early November);

14 - a pullover or fleece for the evening (in the cold season from late November to late January).