The Fifth Commandment of Blogging

Thou Shalt Be Brief

Most people won't be prepared to spend a long time reading your blog. Long blocks of text look intimidating and will make your visitors surf somewhere else. More often than not, you can shorten your entry without damaging it. Set a post length limit for yourself and stick to it as a rule of thumb. MS Word has a word count feature to help you.
If your entry is still long, divide it over several postings (case in point). If that's not working, show a teaser and put the full entry on a separate page.