The hypertext you write is stored in HTML language, which does not contain information about the fonts and paragraph shapes and spacing which should be used for displaying the document.
This gives great advantages in that your document will be rendered successfully on whatever platform it is viewed, including a plain text terminal.
You should be aware that different clients do use different spacing and fonts. You should be careful to use the structuring elements such as headers and lists in the way in which they were intended. If you don't like the rendering on your particular client, don't try to fix it by using inappropriate elements, or trying for example to force extra spacing with empty elements. This may well end up being interpreted differently by other clients and looking very strange. You can in many cases configure the client displays each element.
It is not even wise to assume that your readers will be using a screen-based browser at all. The visually impaired, or those at work or driving, may be browsing the web using their ears rather than their eyes. The "click here" makes even less sense for them.
A few obvious things to do are
I can't give a complete summary of the do's and don't for making a web page "accessible".
Following these guidelines you may find that the end result does not appear on your screen exactly as you would like, but your readers will probably be happier.
There is (2001) a Device Independence Working group at W3C.