Review on L Shape 4-Pin LED Connectors 10-Pack: Expand and Customize Your Lighting with JACKYLED 10mm Wide Right Angle Corner Solderless Adapter Connector Terminal Extension, featuring 22Pcs Clip Connectors for 3528/5050 SMD RGB 4 Conductor LED Light Strips by Carl Givens

You will need to remove all of the adhesive from the end of the light strip you are going to attach. Once you insert the strip into the connector, you need to adjust/push/pull/twist it for the light to actually work. You must be very careful not to tape the end of the jig you are working with or the connector to the wall or ceiling as you may need to make adjustments. If you get the lights working and try to attach the plug to the wall or ceiling, they will no longer work properly and you will have to reconfigure them. Once you've locked the cover and taped it to the wall or ceiling, it's almost impossible to open it back up to adjust the connections as it touches the surface it's taped to. Of course, you'll be working in the corner, so this is a challenge at best. I ended up measuring the fixings and installing the corner connectors before attaching the fixings to the wall and that made things easier. I made a bedroom with a total of 12 corners and it took me about 4 hours. When cutting light-colored tape, be very careful and make sure you cut right in the middle of the intersection. Connectors do not allow errors when cutting. If you're struggling with that, you can turn off the light and leave as much port open as possible. You have to go to the next intersection and just discard the three or four sections of light that you removed. This allows you to connect the full length of the connector instead of half the length. I'll try to take some pictures to explain later.