Before you start your blog, figure out why you want to do it in the first place. Is it for personal or professional reasons?
Some people start a blog to give potential employers a glimpse into what and who they are, a richer impression above and beyond that nerve-racking interview. A blog enables employers and/or customers to get to know you and like you before they work with you. Blogging is an extremely effective way to boost your online professional presence.
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Just remember when you decide to commit to blogging that, like everything else, what you put up on the Web will remain forever somewhere in cyberspace.
Why shouldn't you blog? You shouldn't blog just because you "think" you should blog. If you don't have the time and commitment - stop now. As Li Evans of KeyRelevance says, “If you don't have that passion to sit there and write blog posts and communicate with your audience, you shouldn't be blogging.” Your disinterest will show through in your blog. A stale blog or an abandoned blog does nothing for your reputation.
The rules to blogging are simple:
Be Clear – Simple and concise.
Be Accurate – Spelling and punctuation counts.
Be Yourself – Whether it’s controversial, persuasive or personal, be expressive make it worth reading.