Review your indie author's books.
"But I don't know how to do this."
"I've never written a book review."
"I don't know what to say."
"I'm no good at writing!"
A book review doesn't have to be long and detailed. Sometimes, the short ones are more effective than long, wordy ones. Here's a really short one that I like:
Says it all, doesn't it? In all of its nine words.
If you like to go in to a bit more detail, you could comment on something that you really liked, or something that stood out to you in the book you're reviewing.
About a month ago, I received this review on "Teaching Tori".
Needless to say, I was very happy when I read it because the reviewer gave specific feedback or examples of what they liked. This is invaluable for me as a writer as it gives me clues as to what works in my writing.
So why don't you go check your kindle and see if there are any books on it that you could review? Especially if you enjoyed reading them.
You'll make your Indie author's day!