How do I change Spectrum channels using my Roku remote in Spectrum app?

I searched all over trying to find out how.

Here you go.

http://bfy.tw/BHIQ

I did that. Did not find any useful information.

I'm going from memory here, but there are 2 ways. One is to push the left on the toggle (the one with the select or okay in the middle). Then it's up or down arrow. The second is to use the main left arrow on the top, which can take you to a guide. Unfortunately, there is no keyboard or numbers on a Roku remote.