How to Trim a Bullnose Corner. Tips and tricks for easy removal and install of new trim, how to do bullnose corners, and more! Learn how to add new modern baseboards and door trim with this quick DIY tutorial! Includes how to install baseboards on walls, on round corners, and more! Including how to remove, cut, install, and paint your new baseboards and trim. Installing new modern baseboards and trim is a quick, easy, and cheap DIY home improvement idea! Includes a video tutorial.