What to know
A hashtag should help a reader understand the topic of a post. A camera tutorial benefits from tags about photography and lighting, not unrelated celebrity or trending terms.
A practical approach
List the main subject, a specific subtopic and the intended reader. Select a small set of relevant tags and read existing posts under each before using it. Relevance is more meaningful than an arbitrary count of hashtags.
What to avoid
Platforms change search and discovery interfaces, so no fixed hashtag recipe guarantees reach. Avoid impersonating organizations or joining sensitive event tags purely to gain attention.
Example in practice
A beginner camera post might use a tag for mobile photography and another for indoor lighting. A tag about an unrelated sports event adds noise rather than context. Check that the post actually addresses the topics its tags suggest and revise the list whenever the subject changes.
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