When it comes to being indoors or out, dogs can never seem to make up their minds.

What follows is a seemingly endless cycle of getting up, opening the door, sitting down then doing it all over again to let them back in. Put that on constant repeat throughout the day and it gets a little tiring. A dog door can help end this vicious cycle before it even begins. Instead of dropping a ton of money on one at the store, here’s a quick step-by-step guide to making your own.

Step 1: Measure Your Dog Door

The size of your doggie door will depend on the size of your dog. That means you’ll have to measure him. With your dog standing on all fours, use a measuring tape to gauge the distance from the top of his back down to the floor. You’ll want to give him an inch or two of clearance so he’s not squatting each time he tries to get in. You’ll also leave an inch between the bottom of your doggie door and the bottom of your actual door. Once you've got the measurements down, trace a rectangular doggie door onto your actual door, centered near the bottom.

Step 2: Cut Your Dog Door Into Your People Door

You can take your door off its hinges or, if you’re confident in your cutting skills, leave it erect. Follow of the outline of your pre-measured doggie door all the way around. Drilling holes along the outline might help you get started and provide you with a clear path to follow.

Step 3: Sand It Down

After cutting the outline for your door you’ll likely be left with some sharp edges. To make the door safe for your pup bring out the sander and soften those edges down. Make sure you rid the hole of any wood that might be poking out, which could pose a hazard for your dog. After you’re done sanding the hole feel free to paint it to match the rest of your door.

Step 4: Install the Flap

The flap to your doggie door should be made of rubber. One often suggested material we agree with is the mud flap from an automobile. If you’ve got an old one lying around that’s perfect! Clean it off and paint it if you’d like. The floor mat from a car also works well. Any bendable piece of rubber large enough to cover the hole will do. Using a strong adhesive, attach the flap overtop of the hole in the door on the inside. The rubber mat should be glued along a strip above the hole and hang down over the hole to the bottom. It shouldn’t reach past the bottom of the hole or your dog might not be able to push it both ways.

Step 5: Secure Your Dog Door

While the new dog door is great for allowing your pup to roam in and out freely while you’re at home, you should never leave it unattended when you’re at work or away on vacation. The hole poses a security threat if not properly sealed. You can purchase sheet metal that is large enough to cover the hole for around $10 at a hardware store. Drill holes through each corner of the sheet and in corresponding spots around the dog door, but don’t drill them so deep they go all the way through your door. When you’re not home, be sure to screw the metal plate over your dog door to prevent intruders from using it as an access point. It might not be the prettiest solution, but this will do in a pinch and save you a ton of money over having to buy one and have it installed for you. It'll also keep your dog from interrupting your favorite show when he needs to do his business!