How to create a Custom Master Page in SharePoint 2010

Creating a Custom Master Page in SharePoint 2010 is same as creating Custom Master page in SharePoint 2007.
Step 1: Open your root level site in SharePoint Designer 2010 by selecting Site Actions, Edit in Sharepoint Designer.

Step 2: Navigate to Master Pages library on left navigation and search for V4.master.

Select Master Pages

Step 3: Copy and paste V4.master file and rename it to CustomMasterPager.master
Step 4: Open newly copied master page in select Split mode at the botton of the page.
Step 5: Add or hide any control from this master page like try to hide "Recycle bin" and save your form.
Step 6: Open the SharePoint site in explorer. Open Site Settings page by selecting Site Actions, Site Settings.
Step 7: Under Look and Feel, Select Master Page. If you do not see Master Page link then make sure these feature are activated for the site collection.
a. Should be a Site COllection Administrator to see "Site Collection Administration" section in Site Settings page. Under Site collection Administration select "Site Collection Features". Site Collection Features page opens with all available features for the site collection. Activate "SharePoint Server Publishing Infrastructure".
b. Open Site Settings page again and select "Manage Site Features" under "Site Actions" section. Activate "SharePoint Server Publishing" feature.

Step 8: Under Look and Feel Section, slect Master Page.
Step 9: In "Specify a master page to be used by this site and all sites that inherit from it:"select your custom master page.
Step 10: "Specify a system master page for this site and all sites that inherit from it:" select your custom masterpage. Click Ok and the new master page is applied to complete site collection including System Master Pages.
You can navigate to Home page and notice that "Recycle Bin" is gone.