Gather the ingredients for your homemade bug spray. Catnip contains nepetalactone, which attracts cats but repels bugs naturally. Using dried catnip, which you can find for a few dollars at any pet store, works just fine, but using the fresh stuff is even better. Vanilla is a scent that's disliked by several types of bugs, including ticks. Essential oils such as lavender, rosemary, lemongrass, and citronella also keep bugs away while adding a wonderful scent to this insect repellent.