SEO is based on what people generally search. Now the blog which you have created must be based on some area of interest, and people must be searching somewhere or other for it. So try to pick the word that is directly related to your subject...for example,if you are writing on technology,use the word tech if not the entire form of the word, and then the word synonymous to blog, writing, information etc. Try to get a short name clubbing two or more ideas.
Try these sites, which offer effective tools for Domain name suggestions.
Hope they work for you. All the best.