How to create data warehouse

I want to create data warehouse , it includes 4 types of databases (sqlserver,oracle,mysql,access) & i have already store data in these databases but how can i create datawarehouse using sql server??? plzzzz help me.......

Create a new database in SQL Server, call it EDW. Extract (E) all the data from your source datababases, transform (T) it to the new enterprise data model in the EDW database, and load (L) it based on user requirements. Most folks using SQL Server like to use SSIS for their ETL tool although I'm not sure how well it connects to non-Microsoft third party databases. You may find you need to hire a couple of people to help in this process. Project managers, data analysts, data modelers, ETL developers, and reporting people are a few of the more common roles. Hopefully your question didn't imply that someone expects you to do the job of five people minimum. Good luck!

but how can i create datawarehouse using sql server??? ???

Buy this:

http://www.kimballgroup.com/data-warehouse-business-intelligence-resources/books/microsoft-data-warehouse-dw-toolkit/

Read.