Perhaps you have a more specific question?  The question you are asking here is a little to general to facilitate an actionable answer. 

When deciding what to write about, I would suggest you select topics about which you have more knowledge than the average person and those topics also be of some interest to a given audience. 

Good luck, we hope you will post the link, so we can enjoy what you write!

MP

As middle suggested, write what you know about. (Unless you want to ask an intelligent question.)

Stay away from trite overused phrases that don't say anything. (Example: What would Jesus do?)

Be concise. Edit your own words. Lengthy reading does not attract alot of people. Takes practice.

Wear a thick skin. Not everyone will agree with you. You can post "the sky is blue" and someone will debate your statement.

Most importantly, have fun.

LoveVintage, if you want to be seen, I would suggest that you do it right here, like I do.

looking for a place to blog ? Type in blog,free blog or typically your provider has a blog spot~ like yahoo blogs. There are many,many places to choose from.

mp's idea is the way to go,networking (reading others blogs and linking with them) is a good way to build up a reader base,and unlike here,if you get a comment~wow!!! You did good.

Best of luck!