The Sawyer kit is splendid for insect bites. It's efficacy with snakebites is unproven and subject to debate. All of the Cutter type 'cut and suck' kits are utterly useless and cause more harm. If you apply a tourniquet to a limb you will lose it. Your best aid is to study the venemous sankes and insects and understand their habits and how each toxin works ; neuro, muscular etc. There is only one agreed upon course of action; First, remain calm. Second evacuate to a proper medical facility asap.