We are all really willing to help...
But first, I'm curious - why are you "required" to upgrade the switch?
What version are you "required" to upgrade it to?
Typically we have a specific reason for upgrading the IOS on a switch - new feature, bug fix, security fix,etc. Then we know exactly which version we want to upgrade to, because it would have been in the bulletin telling us that there was a security issue, or we have researched a bug for the "fixed in version xxxx.yy.z"...
Else, you may be "required" to upgrade for a class assignment. If this is the case, then I would assume the class would have access to the upgrade IOS..
All that said, for a Cisco Newbie, you may find Cisco Network Assistant useful to do upgrades with:
http://www.cisco.com/go/cnaWith CNA, you can literally drag and drop the IOS image from PC to the switch, or use the Upgrade tool. It is all GUI based, and easy to figure out.
Otherwise, you can get the latest IOS, or any older version that has not been deferred, from here - NOTE: requires a CCO account login, with download permissions. Only comes if you have an active service contract (i.e. SmartNET) and have registered:
http://tools.cisco.com/support/downloads/go/Redirect.x?mdfid=268438038Expand LAN Switches - Access
Select Cisco Catalyst 2960 Series Switches
Select the exact model switch
Select IOS Software
Select the Latest Releases (122-53.SE2)
Determine if you want the .bin file or the .tar file - with or without crypto (SSH, may be export restricted)
(hint - use .bin file for manual upload to switch, use .tar file for CNA upgrade)
[download now]
Go to download cart, and complete the acknowledgments and complete the download process to get the IOS.
Step-by-step guide to upgrading the switch, using multiple methods - NO LOGIN required :
http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/release/12.2_53_se/release/notes/OL21141.html#wp697759
