Once you've been an indie author for a while and published a few books, you begin to gain a certain amount of wisdom and experience. You know, for example, how to format an ebook, where to go for cover art, which Goodreads groups to use to find reviews. The indie author community is largely a place for sharing information, and there are times when it all feels friendly. And one day, you may be compelled to take some other indie author under your wing and share your valuable experience with them. You may, one day, feel the need to give out a little unsoliticed advice -- with the best intentions in mind, of course.
I warn you not to do this...no matter how tempting it might get.
Everything You Can Do...
Say you're hosting an indie author on your blog, or you're being hosted on their blog. Suppose, during the course of getting all of this organized, you notice something on their blog or Twitter profile or Amazon page or whatever. Something...that's just wrong. Maybe the blurb is all wrong, or the cover is crazy-looking, or they're just misunderstanding Twitter all to hell and back.
You know better. In fact, you made a similar mistake and learned all about it. You know exactly how to fix the problem...and it would be fairly easy to do. So do you tell your indie author colleague, and grace them with the value of your knowledge and insight?
Absolutely, unequivocally, no. It doesn't matter how nicely you phrase it or how well-intentioned you mean it. If you give you unsolicited advice to another author, it's going to be interpreted as a criticism 9 times out of 10. Of those 9 times, 8 of them are going to go poorly when that other author tells you off (or worse, points out your own flaws). It's just a bad situation for everyone. They won't take your advice any way except the wrong way, they certainly won't follow it, and you're just going to wind up feeling bad and frustrated. It could even lead to an argument and it could very easily ruin the opportunity to work with this author in the future.
Wait until they ask. If they ask you what you think, they're opening the door and they expect to get some criticism back. When you give unsolicited advice, it very often feels like an attack to indie authors -- who are, generally speaking, a little nervous and unsure of their art in the first place. If they don't ask, they don't ask -- and it isn't your place to give them the help they need. If they're not asking you, it's because they don't want your help.
So make it easy on yourself, and simply don't give out unsolicited advice. It's almost never received well, and you have lots of other stuff to do.