save, then click the red link, draft1, after you save the page. I used "draft1" for this example but it can have almost any name you like. Do NOT forget that first forward slash or you will put the page in the main namespace as a regular article and will have to ask for speedy deletion if you save anything you write. A red link means a page has no content and if you just navigate away without saving any content the page will not be created and there is nothing to delete. Copy the source for the article you want to edit to your sandbox and perfect your edits there. Be careful when going back to the article that you do not inadvertently revert edits subsequent to your copying the page. Once you are more experienced you can forsake the sandbox for smaller edits and edit directly in the article remembering, of course, to proof-read thoroughly using "show preview" before saving the page. If you need help creating a user subpage, you can get assistance at WP:UPH.