Component or whole URL, %20 or plus, single or double encoding. The distinctions that cause real bugs, explained with the cases where each one bites.

Gather the URLs, prune the list to the ones that deserve to be there, generate valid XML, upload it, and submit it once. The whole workflow in ten minutes.

The sitemap protocol is five tags long. Here is the whole format, the rules that trip people up, and the handful of cases where writing one by hand beats generating it.