Type or write (neatly) your assignment on notebook-sized paper.
If you handwrite your assignments, use a pen, since penciled writing is
often hard to read.
Make sure that the grader can clearly understand what the problem
is without having to look it up.
Be sure to leave plenty of space for comments. Usually you should
leave a fifth of a page per problem, plus nice-sized margins.
Make sure that you cut off the squigglies on paper ripped out of
a spiral notebook.
Use full English sentences where appropriate (namely almost
everywhere, including in mathematical proofs or derivations). Proofread
what you have written to make sure it makes sense.
Show enough work so that any student in the class can follow your
solution. Just writing the answer is never enough.
When the problem is to write a procedure, you should do more than
simply write the procedure. When you're doing the homework, you should
write the procedure, test it, debug it, rewrite it, test it some more,
and so on. When you write up that problem, you should say what the
procedure is supposed to do, present the procedure, explain why you know
it does what it's supposed to do, and describe clearly how you tested
the code. Again, just writing the procedure (answer) is never
enough.
Use diagrams, tables, programs, and calculations as supporting
components of English writing, not in isolation. Remember that your goal
is to communicate clearly, and that the appearance of these technical
items plays a role in this communication process.
Don't try to bluster your way through a proof or a procedure.
Instead, if there is a gap in your proof, acknowledge it. If you have a
bug in your code, say what it is and why you think it happens. Better
yet, go talk with your professor beforehand and see if she can help you.