**Please note, I made this tutorial on an XP Professional system. If your screens are different, or if my procedures are innaccurate for XP Home (they're slightly different), please reply to this post, or start a new post.
I believe File and Printer Sharing are on by default wit XP Home, so you can go straight to sharing a folder.
Double click My Computer (you may have to go to Start, then click on My Computer (if you want, you can right click on My Computer in the menu and select Show on Desktop)), then double click on your C: Drive to see all of your folders. Right click on a folder you want to share. Select Sharing and Security from the menu that comes up.
To check or change permissions, click the Permissions button on the Sharing tab of the folder Properties that opens up.
You'll see that the default is for all users to have Read Only permissions. This may be acceptable, but if you want to change the rights, you may do so. Click Ok and you're set.
For Windows XP, you may also have to permit traffic through your firewall (assuming you have XP Service Pack 2 installed, or have enabled the XP firewall).
Go to Start, Control Panel, and in Control Panel, double click Add or Remove Programs.
Click Add/Remove Windows Components on the left of the Add or Remove a Program window.
In the Windows Components Wizard, scroll down to Networking Services, high light it by clicking on it, then click the Details button.
In the Networking Services window that opens, click the box next to Peer-to-Peer, then click Ok, and Ok again. This should set your firewall to allow Peer-to-Peer networking. That's it! You're a Networking Guru now!
There may be a Part 4 on Wireless Networking, if it seems like there is enough interest. Please post your feedback!