This tutorial was made to help guide you through the installation of Custom Themes with Themely by @erman1337. Download Themely from here. (It is recommended to use the CIA version.) Go to 3dsthem.es, find a theme you like, and download it. Take your SD Card out of your 3DS/2DS and put it in your computer/Mac. Drag the ZIP file you just downloaded to the Themes folder on your SD Card. (With Themely, it is unnecessary to extract the data from the ZIP file.) Drag the Themely CIA to the CIAs folder on your SD Card. Take your SD Card out of your computer and put it back in your 3DS/2DS. Turn on your 3DS/2DS and install the Themely CIA using your favorite CIA installer. Start Themely (It may black screen the first time you start it. If it does, force the 3DS/2DS to shut down by holding the Power Button and try again) and find the theme you downloaded in the list. (If there is only one theme in your Themes folder, there will not be a list.) Press the A Button to install the theme. (Hold R and press the A Button to install the theme without BGM.) Press Start to exit Themely and press the HOME Button to go to the HOME Menu. You should now see the Custom Theme you installed on your HOME Menu. You now have Custom Themes. To install a new theme, download a new theme from 3dsthem.es and install it using Themely. If Themely isn't working for you, you can either post about your issue here or try CHMM2 by @Rinnegatamante. (CHMM2 is no longer receiving updates, therefore it is very broken and not recommended.) If you have a feature suggestion for Themely, you can post it here. Themely should have a Theme Downloader Soon™, so when that happens, this tutorial will be updated. Themely should have Theme Shuffling Soon™. Themely will check for updates when launched. If there is an update, Themely should download it.