Login the twitter website with your twitter account details.
Settings
Once you logged in, you will see home page. Click the 'Settings' link in the header menu.
Connections
In the settings page, click the 'Connections' link.
Developers Section
In this page list of applications
will be displayed. In the right side of the page, you will see
Developers section. Click the 'here' link that section.
Register a new application
In the next page that comes, click the 'Register a new application' link.
API Form
Application registration form will be shown. The following are necessary fields to be filled up.
API Credentials
Then you will get Twitter Consumer Key and Consumer Secret.