To apply a discount to your members first you have to activate the advanced event configuration ... once you do this you will see the quick navigation bar expands to give you more options.
Click on the % icon which will quickly take you to the event discount section, open the pop. up to set up your discount there! If you are applying this to your members please do not forget to upload your member number list ... you can do this in the my assets section https://organisers.horsemonkey.com/myassets
Here is how these steps will look π