Summarize this article in one sentence.
Since hashtags function similarly on all supported platforms, the account you choose is really up to you. Keep in mind that hashtagged posts on private accounts won't show up in public searches. Remember that you'll want to make sure the post is relevant to the hashtag you plan on using.  On Instagram, Pinterest, and YouTube, your hashtags will go in the description area below your visual post (e.g., the photo or video). Tumblr posts require hashtags to go in a separate section of the post (not the body). You'll see a tag section at the bottom of the "New Post" template. You can also use hashtags while commenting on most posts. To do so, you'll type a # sign, then type in the word or phrase you wish to hashtag without any spaces or punctuation. The hashtag will turn into a clickable link in your post. Now your post is discoverable by people searching for that hashtag. Doing so will take you to your selected hashtags' pages, where you can view the public discussion occurring around said hashtags.

Summary:
Open your social media account of choice. Create a new post. Type in your hashtag. Publish your post. Click other people's hashtags.