1. Right-click on the menu bar of the Putty screen and select “change Settings”
2. Go to Session and click on Logging, select “Log all session output”
3. Click on Browse and choose the location and name of the file (I like to place my config file on my desktop – C:\Documents and Settings\Administrator\Desktop\config.txt)
See https://akhpark.wordpress.com/2013/02/08/show-running-config-without-more/ on how to disable more on cisco devices.