Links are how a reader moves from one article to the next. They also interrupt the sentence they sit in. A good link does both jobs without making the reader stop to decode it.
Use the destination as the link text
"Read the font-size guide" says where the click goes. "Click here" says nothing until the reader hovers. Screen readers often list links out of context, so the words of the link have to stand alone.
Link when it serves this article
Send people onward when the other piece answers a question you raised, not to fill a quota. One relevant link is more useful than five that wander off the point.
Leave the sentence intact
A reader who does not click should still understand the paragraph. Put the link on the phrase that names the idea, and keep the surrounding sentence complete.
Before you publish, click every link. A dead one is a small broken promise in the middle of an otherwise careful page.