Your viewers can gift you diamonds during your live videos. You can also gift diamonds to show streamers that you appreciate them. To see how many diamonds you have collected, click on the profile symbol in the top right-hand corner of the app. Now you can see the number of diamonds you have received under your credits.
Here you have the option of redeeming your diamonds in the form of a cash or credit reward. A cash reward is where the diamonds you have collected are paid out to you in cash. If you select the credit reward, you can convert your diamonds into credits and use them to give gifts to others in their streams.