To change the blade on your DEWALT DWHT10295 Utility Knife, follow these steps: Extend the Slider: Push the slider all the way forward. Press the Release Button: Press and hold the release button (usually marked with an arrow). Remove the Old Blade: Pull out the old blade while holding the button. Insert the New Blade: With the slider still extended, insert the new blade and push it until it locks into place. Release the Button: Release the button and ensure the new blade is securely locked