just keep the extra crickets in a small rubbermaid container (or larger if you plan on ordering more than 120 crickets at a time) drill holes all over the lid (make sure the holes are not more than 1/8th of an inch so crickets won't escape), or you can cut away sections off the lid and cover the large whole with fine aluminum screen (just ducktape it on or use glue gun).
Tear up a egg carton or two and toss it in, use two shadow dishes, one for either home made or store bought dry gutload and the other for fresh mixed greens, with carrots, or potato or orange slices to act as both extra food and moisture for the crickets. Depending on the age of the crickets you are buying, the crickets will grow and live for weeks to month or two. Just wash the food dishes every couple days and give new fresh food daily (the dry stuff can sit for a few days before changing, unless you notice alot of poo in it).
Once every week or so (or every other week) idealy just when you get new crickets or just before, wash out the entire containter and put in new egg carton. This way it keeps down the smell. PIck out any dead crickets in the container daily as well. Dead crickets rot fast and causes most of the smells.