What makes a quality comment?

Commenting on the Steem blockchain(Steemit.com) can be one of the most important skill sets for any new Steemit user. When commenting on Steemit we can gain rewards, followers and even spam/phishing links, these will usually be 'greyed out' or will contain non-relevant URL links usually without a '.com'. Cheetah, mack bot, @spaminator comments or flags on certain comments and posts can be a good indicator of spam.

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How can we avoid making spammy comments?
Well, first off avoid using links, especially ones that are not relevant or soliciting stuff. Second, read the post you're making a comment on, does your comment pertain to the post, does it have a 'complete sentence'? Meaning was proper punctuation used to express a complete thought?

Let's pretend I made a Steemit post about pasta and we are reviewing good and bad comments made.
Here are some good examples of comments:

Hello, I really enjoyed this post about about pasta. My favorite food is Macaroni and Cheese.
I am also a pasta fan. I will follow you in anticipation of more pasta posts. I will also post about pasta on my Steemit page, if you wish to follow me as well!

Here are some bad examples of comments.

follow for follow
vote for vote you agree
https://steemworld.org/@dynamicgreentk for all your steemit needs. Upvote my stuff while your there.
Https://www.dynamicgreenindustries.ohyeahdontclickthis

When should a comment be made?

There is an old saying from the movie Bambi that says "If you don't have anything nice to say, don't say anything at all." This is a mere guideline for interacting with people in life. Often times conversations can be come heated, its best to avoid 'heated' or rude comments on. We can earn Steem, Steem Backed Dollars, Steem Power and even followers from making quality, non-spammy that are relevant to the post we are commenting on. Best to avoid negative or rude comments, especially ones that don't pertain to the post as those can be viewed as spam and will usually leave you with out any upvotes and might cause a flag to be thrown on your comment.

Anytime you see content or posts on Steemit that excite you, that is when you should comment. A very great strategy on Steemit is to make comments on content that is relevant to you and more specifically on individuals that have similar interests as you. Long term Steemit growth should be the goal and makimg quality comments regularly will help achieve this for most.

Do you want to get a whale or dolphin's attention? Don't just tag them in your posts, read their posts and make comments there reguarly. Dont get discouraged if your comments are not noticed at first, chances are there are hundreds of comments. Try adjusting your @ginabot settings for the whales you want attention from by getting notified on when they first make post. Commenting when a post is 'fresh' is the best way to do this, really for any Steemit user.

Please reference this post from @isaria for even more information on this subject!
https://steemit.com/steemit/@isaria/help-for-minnows-and-new-users-the-importance-of-meaningful-and-valuable-comments