Writing clearly is easy–once you figure out what you want to write about and what you want to say about it.  Those are the hard parts and once you get them straight, the rest is mostly common sense.  For example--

Most things you'll write will have a subject and will say something about that subject.  The subject of this thing is writing clearly.  By the way, you can forget the teacher-word "topic."  Forget "topic sentence" and "theme," too.  They're real words, but they've been misused by generations of teachers, and now they just confuse us.  Stick to "subject" for now.

Choose a title that identifies your subject, at least indirectly.  For example, look at the title of this page–which I hope told you what the page is about.  (My favorite contrary example is a poster with the title SEX.  The first sentence is "Now that I've got your attention, let me tell you about the Campus Crusade for Christ.")

Usually, write your main idea about the subject at the beginning and follow it with the explanation.  Not the other way around–unless you're writing a mystery story.  Your main idea about the subject is the biggest, most general thing you can say about it in a sentence or two.  In academic writing, it's often called a "thesis," but it's still just an idea.  The main idea of this paragraph is that it's usually best to put your thesis at the beginning.  The main idea of this whole web page is that common sense leads to clear writing.  (Click here to find out about introductions and conclusions [coming soon].)

Use the smallest word that will do.  In other words, eschew unnecessarily grandiose terminology.  (There!  See what I mean?)  I have to admit that some people think you're smart if you use big words on them.  The question is, Do you want to be clear, or do you want to fool people?

Pick a name for something and stick to it.  Don't use synonyms for a word, because after changing the term to a synonym (as I've changed word to term) a few times (and next, changing term to office) you're likely to end up with the original election lost and the reader thinking you're writing about a new contest entirely.  (Huh???)  Well, I hope you get the point:  there are no natural true synonyms.

Make transitions clear.   Clear transitions lead your reader from one sentence or paragraph to the next, showing how the second is related to the previous one.  This paragraph, for example, is related to being clear, and that's what the whole web page is about.  But what about the transition from the previous paragraph (about synonyms) to this one?  Frankly, I'm not too worried about that transition because I'm writing all of these paragraphs so they can stand on their own, independent of the others but related to writing clearly.  But within this paragraph I have to be sure that you know how the sentences are related--or risk confusing you.  So I've used words like "But" and "So" and "for example" and "Frankly" to help with transitions.  I hope that's clear.
 

VISUAL THINGS
Consider using headings if they will help your readers see at a glance where they are and where you're taking them.  Headings (also called subheads) are especially helpful when you start a new section.  There's one above this paragraph.  (Some persons still aren't used to seeing headings in academic writing–but they need to wake up.)

Spelling, punctuation, indentation, and the like are also visual things.  But they're another subject entirely.  They have almost nothing to do with writing clearly, but they have a lot to do with how writing affects readers–just as how we dress affects the people who see us.  Look for info on them here [coming soon].
 

GRAMMAR
Grammar has nothing to do with writing and everything to do with politics. Read about it here.
 

CAUTION
These are general principles.  Sometimes they don't work.  The one rule that always works is:  Do what works.  That is, do what you need to do to get your ideas across to your readers.  For that, you have to know what your subject is, what you want to say about it, and what your readers are ready to see and understand.
 

Sorry, this is it for now.  More is on the way.  Please let me know if anything is wrong or screwy in here, or if you think of things I should add.  --Don Maxwell
 
 

A Few Clumps of Writing Words

introduction
main body (or just body)
conclusion

subject
theme
text
topic

article
story
essay
paper
composition

thesis
dissertation
exposition
argument
document

report
monograph
discussion
explanation
discourse
treatise