Okay, let's be honest. It's really not that hard to take a picture. That said, if you've got a camera, some white walls and a tripod/another person, you can probably get your own visa photos for cents (pesos, halfpence, etc.) instead of paying the drugstore $8.99 for two.
ePassportPhoto is a free service that helps you set up your own passport photos, according to a country's specifications. They've got a little guide on how to take the photo, and will help you adjust the photo once it's uploaded. Though they'll try to sell you their Pro service, just make sure to click "No thanks" after you finish editing your photo. You'll then be presented to a screen where you can download the photo file (which contains four passport photos) onto your computer.
The file, which is conveniently proportioned for a 4x6 inch photo, can be loaded onto a USB and taken to the nearest photo kiosk. The cost ends up being 31 cents for four photos, which I divide by using a pair of scissors (look, magic!). I generally keep some photos floating around, for visas and applications that randomly pop up.
I've actually used the photos to apply for employment and tourist visas in Vietnam, Hong Kong and some other places successfully. You'll just have to check the photo size specifications on your application for particulars. And stay away from the Instagram.