A pop-up sink stopper has become one of the most popular ways to stop water from draining out of the sink. Installing one of these stoppers is fairly simple and requires a few basic tools. Firstly, you'll need to remove the existing drain strainer or stopper from the sink. Next, you'll need to measure the length of the drain opening in order to choose the appropriate size of pop-up drain stopper. Depending on your type of sink, you may need to adhere the bottom of the stopper to the sink with silicone caulk. Once the stopper is in place, you'll have to adjust the height of the rod in order to ensure that the open and closed positions of the stopper are correct. Then, you'll have to connect the drain stopper's linkages to the lift rod assembly, which should come with the new stopper. Finally, you'll need to test the stopper to ensure that it is functioning properly. If you have questions about installing a pop-up sink stopper, you should consult the user manual that comes with the stopper or consult a professional plumber who can help you with the installation.