Summer is the perfect time for throwing open the windows and airing the place out—which is why it’s so important to have a screen in good condition that will keep bothersome insects out. Over time, your screen might have to be replaced. If that’s the case, here’s a step-by-step guide for doing the job in 30 minutes flat. The tools you’ll need: – Screen material – Screwdriver – Vinyl spline – Pliers – Scissors – Utility knife – Screen rolling tool Step 1 Remove the screen frame from the window. With the screwdriver and pliers, remove the vinyl spline from its channel in the aluminum frame. If the spline is still flexible and in good condition, you can reuse it. Otherwise, you’ll have to buy a new one. Step 2 Once the spline is removed, you can take out the old screen. Unroll the new screen material over the aluminum…