Search Service application - SharePoint 2010

Create a Service account with Domain user and DBO permission.
Register this account in managed accounts through CA.
Create new search service application --> CA --> Manage service application --> New --> Search service application --> Enter the name of service application --> Select the service account for this application --> Select new or existing application pool --> OK

Click on Search administration , verify the default content access account and enter the Contact email address, Content sources.

By default the service account selected while creating search application is the default content access account. You can change the default content access account through below step:
Search administration --> System status -->  Click on the account which is just right side of that default content access account.
In the same way change/enter the contact email address.

Create content source --> Click on content source in search administration --> New Content --> Select the content source type --> Add the URL  --> Define the Crawl schedule incremental/full -->ok

To get the people search:
Just add the default content service account permission as "Retrieve people data for search crawl" at User profile service application. Here are the steps:
User profile service application --> Administrator --> add  default content service account permission as "Retrieve people data for search crawlers"
Provide FULL Read permission to this account at all the required web applications.

If you don't have basic search page then create it now, here are the steps:
Browse the top level site --> Site actions --> New Site --> Select "Enterprise Search Center"  --> Enter the name and URL --> Ok

Create Enterprise search page --> Central Administration / Application Management / Site Collections, click on Create site collections.   Ensure you are creating the Site Collection below the relevant Web Application. Enter your Title, Description etc and select the Enterprise Tab under Template selection.  Select the Enterprise Search Center, specify your site collection administrators and click OK.

Secure Store Service -SharePoint 2010

SSS: Secure Store Service in SharePoint 2010 replaces the single Sign On feature available in SharePoint 2007. It is a shared service that provides storage and mapping of credentials. It helps to correct the external systems through secure store data, it is specific to individual or group. SSS can be used to store and map the user credentials required by external system.

Following services can use SSS in SharePoint 2010:
Excel Services  
Visio Services  
PerformancePoint Services  
PowerPivot for SharePoint 2010   
Microsoft Business Connectivity Services

It is recommended to run the SSS in a separate application pool that is not used for any other service, Run the Secure Store Service on a separate application server that is not used for any other service.
 Before generating a new encryption key, back up the Secure Store database

Secure store service and claims authentication

Steps to create SSS:
Create a Service account and provide DBO permission at DB server.
CA --> Manage Service application -->   New -->Enter Service application name --> Enter DB server and DB name --> Enter or select the application pool name --> Select the service account for this SSS through managed account.

Once the SSS is created enter the Target ID --> Set credential and Permission