Out Of the Woods
This view of the Carrie Nation Memorial Forest is brought to you by courtesy of the Lee company. The same people who make the Big Stopper, the Little Stopper, and the Enormously Popular System Of Graduated Filters. They also make large rolls of transparent and translucent plastic sheets that you can put over studio lights to change the colours.
You can have mild filters and wild filters - the weak ones compensate for inadequacies in the lighting and the wild ones compensate for the lack of artistic ability. The rolls are big enough that you can cover the front of a soft box or cut them up to make reusable ones for the smaller reflectors. I sandwich them between bits of matt board or plywood and then hook that over the rim of the reflector. Crude, but effective.
Beware of the heat generated by the modelling lights - Lee make heat-resistant gels for theatrical use that can withstand the stage lights - if you have a choice get this kind.
Roscoe also make this sort of material, and sometimes we have interesting packets of pre-cut gels here in the shop. Heck, they're cheap enough and you never can tell where a colour will be needed. You can wrap them on a speed light and do it out in the field as well. A splash of green on a bride's face at the altar is always a nice touch...