Call your local credit bureau and ask for a report on yourself AND your spouse, or co-buyer.  The reason for this is to find out FIRST if there is any erroneous information on the report, BEFORE you fill out a loan application with a lender.  Make sure everything reported is accurate. If you find any errors take steps to correct them IMMEDIATELY.  At the very least, you may be able to insert into the report an explanation of the disputed item(s) in the report.

Ask your agent to email you selected properties.   Your REALTOR®  has the best source of current properties for sale.  Your agent needs to keep you updated regularly. 

You ought to do drive-by's of the list of properties your agent provides.  Shopping online for a TV or computer is one thing.  But buying a house takes getting in touch with the neighborhood and area you want to live in.  Neighborhoods vary greatly.  What might look like the perfect house on the Internet might be located on a busy street, or otherwise may not be appropriate for your needs.

Get all your cash or gifts for your down payment ready and in order.  Don't forget about the up-front money you'll need for property and home inspections, as well as closing costs.  (Your agent or lender can give you an idea of how much cash you'll need at the close).  If you have to liquidate stocks, or get money out of a retirement plan, CD's, or from some other source, make sure you know the time frame for getting the money out so it's available for your down payment at the close of escrow.

Refrain from buying any big ticket items such as a new car or furniture.  These can kill a loan if your debt to income ratios are too high.  Pay down your credit cards - and don't apply for any new ones. Don't make any major purchases on credit - buy the furniture or car later after you close escrow and take possession of your new home.  

Your REALTOR®  and loan officer can help you determine how much home you can afford.  Most importantly, don't shop for homes that are out of your price range.  Stay focused on homes within your means.  In our coastal community, most people who move here from other states or even from other locations within California are probably going to be surprised at the cost of real property.  Most people that move here realize they are making a decision about quality of life.

Ask your REALTOR®  to go over the contract forms and other documents.  Be sure to read all the fine print and ask questions.  California has many consumer protections that require various disclosures and other kinds of information designed to help you, the Buyer.  Look these documents over carefully, and ask questions if there is something you don't understand.  Remember, your REALTOR® is not an attorney and cannot give you legal advice or make legal interpretations in the contracts and other documents.  If you feel you need legal advice, please consult a qualified attorney to assist you.