This is a good game for small groups as there are only so many food color “blends”.
Each participant gets a squirt gun filled with a different color water. The larger pumping guns are best, but this calls for a bigger budget. If using a small gun, each player will need a jug of “ammo” so they can reload.
Layout a course beforehand, preferably in a semi-wooded area. Have the players walk the course to familiarize themselves with it before you put the targets out. Place inconspicuous targets all around (on the ground and in the trees). I used a heavy paper and cut out animal shapes mounted to craft sticks. The larger the “target” the fewer pts. it scores. Let one player at a time go out, while the rest are otherwise diverted – set a time limit by walking the distance of the course and take into account that they will need time to seek out their prey. Count up all the colors found on each target, and the player with the most points wins. You could also just count hits, and forget the point values.