You've started your blog. Your blog isn't just an avenue to share your thoughts about a particular area but an opportunity to market your business...
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Yes, writing for self and for others can often prove a lucrative venture. Some of the things that wanna be freelance writers usually need to know to launch their freelance business / career fast include just using some of the posts on ones blog as samples, Googling some blogs in the same niche (that are bigger) and emailing them using email templates like the ones I have linked to.