It is so sad to see some of the blurbs provided for books published here on Lulu.
Your blurb has got to be word perfect. It is your store window; it is supposed to entice people to buy your book. If it is boring and full of spelling and grammar errors then the cause is already lost. You might as well have a blurb saying 'do not read this book'. I want to read books in English; if the blurb is written in very poor English (mixing tenses, incorrect use of the apostrophe, incorrect capitalization, etc.) then I will shy away from the book.
I would suggest that the blurb is written while you are writing your book and not as an afterthought.
I am all for anyone having a go at self publishing but one has to be realistic. If your product is very poor you can't expect much in the way of sales.