1. Start with the URL. ex. http://www.dhmo.org/.
What is the domain? .org commonly used by schools, communities, projects, and for profit organizations.
Other common possibilities include .edu for education .com for commercial or .gov for government.
There might also be a country code (.uk, .de, etc) which are not tightly controlled.
Who is the publisher? http://.dhmo.org/ The publisher is the sections of URL between http:// and /.
2. What information can you find on the page?
Look for about, philosophies, mission statement, background, biography, FAQ. (frequently asked questions) or other similar wording. This section should provide information about those responsible for the content. Finding one of these can allow you to find more information about the author, organization, etc.
What is the copyright date?
Many sites list this at the bottom of the page and might have a single year, or a range of years.
dhmo.org has a FAQ page and on the bottom of any of the pages, it shows a contact email and that "Tom Way" is the copyright holder. The copyright was last updated July 2015. The site also lists the curious sentence "Note: content veracity not implied." Put in simpler language, the information on this site is not accurate.
Important to note, particularly on the FAQ page are links to other sites. The listing at the bottom of the FAQ pages that out of the 7 linked pages 2 are marked inactive and a further page returns a 404 error (page not found). When pages links do not function, it is a sign the page is not well maintained.
3. What do other sources say about the webpage?
Alexa.com Can provide some background information such as global rank, nation of visitors, contact information and how long browsers stay on the page.
Run a Google search. A search for http://www.dhmo.org/ reveals a Snopes page as the second result.
4. Review your results and decide if the webpage is a useful and credible source.
In most causes this webpage would not be a good source. It would all depend on the topic, if one were investigated webpage frauds it might be helpful, but a topic on dangerous chemicals would not find it a good choice.