All games that are mod-able will need some tools for you to edit the game files or data. You can find these tools online, or purchase them if possible (like the tool we use). So far, all Android games that were modded can be customized using a hex editor like ES Data Editor.
If you're familiar with this kind of tool, then go ahead and search for mods on Google Play Store or check out other forums/websites around the internet. Mod APKs contain various types of edits so you might want to download more than one Mods in order to achieve your desired outcome... well at least until someone makes an all-in-one mod APK for you.