Looks fairly easy to make once I figure out where to buy those oils, guessing a health or grocery store.
I hire out the exterminator once a year to spray the house and it costs about 200 bucks, the stuff he uses works well. I've started thinking, why not create my own stuff and do it myself? It will cost less, and I can do it more often. I have a phobia of spider webs so this is why I don't want spiders, regardless of how good they may be. If this DIY repellent works for other bugs too then that's a bonus.
I was thinking I could also use a super soaker gun or some kind of other pumping mechanism instead of a regular spray bottle.