Steps:
-Open Cydia
-Tap on the “manage” button at the bottom
-Next click the “sources” tab, in this area tap “edit” button at the top right corner then click the “add” button at the top left
-A pop up box will appear on your screen and you will be able to add your source into the window. After adding the source tap on the “add source” button, it will then be installed and added to Cydia.
Sources: (Add these sources at your own risk)
sinfuliphonerepo.com/
cydia.xsellize.com/