I feel you will benefit quite a bit from the free educational information at http://www.myfico.com/crediteducation/improveyourscore.aspx
In general, keep your payments current and payoff revolving debt. Don't look for furniture or new cars until you close. Don't rate shop and get a lot of inquires. DON'T Co-Sign for anyone for anything (whether friend, family, or other). Other than that, it's really a matter of waiting. good luck!
I am suspecting you are going on the premise that you need a 640 score to purchase....Wells Fargo does have a product, if you qualify that would allow you to close at around a 500 credit score. I am also suspecting you have been babysitting your bureau(credit report) and have had any incorrect items removed or corrected. Also speak with your lender if you have recently paid any of your credit cards down to zero. This is not typically something that will raise your score, but actually lower it. If you make any corrections, changes to your credit items, your lender should be able to do a rapid rescore, which can take approx a week...If you dont have a lender or a "good" agent, feel free to give me a call and I will assist you as I am able.
Good Luck!!! Suzanne with http://www.TheMLSonline.com 612-309-0884
There is no guarentee as to how long it can take to bring your score up 52 pts but there are cases where this is accomplished in 90-180 days. I look forward to hearing from you-
Executive Real Estate Professionals