How to enable the audit log in SharePoint 2013

To enable the audit log by using Central Administration

·         On the Central Administration home page,

·         In the Application Management section,

·         Click Manage service applications.

·         Select the Secure Store service application.

·         On the ribbon, click Properties.

·         From the Enable Audit section,

·         Click to select the Audit log enabled box.

·         To change the number of days that entries will be purged from the audit log file, specify a number in days in the Days until Purge field.

·         The default value is 30 days.

·         Click OK.

Configure audit settings for a site collection

Please use the following link in which Microsoft has given a very detailed description that references each and every minor point regarding audit settings:

It consists of:

·         Auditing event information

·         Trimming the audit logs (new enhancements in SP2010 and SP2013 as compare to earlier versions)

·         Configure audit log trimming

·         Configure events to audit

http://office.microsoft.com/en-us/sharepoint-help/configure-audit-settings-for-a-site-collection-HA102866204.aspx  

View audit log reports

Following link will help you to understand the following points:

·         Events available for audit log reports

·         Available audit log reports

·         View audit log reports

http://office.microsoft.com/en-us/sharepoint-help/view-audit-log-reports-HA102772739.aspx  

Please let me know in case of any queries/questions so that we can discuss and sort it out quickly.

Thank you