Do:
1. Label your graphs, axes
2. Present your data (do not just say "I did that")
3. Rather than using colors on graphs, use different line patterns
4. Describe concisely your procedure for solving the problem, and present your sources
5. Always be concise, but not at the expense of clarity
6. ALWAYS INTERPRET YOUR RESULTS (if the text says "plot ..." then plot AND explain "we can see on the graph that ...")
7. Be systematic, show your solutions on a per problem basis (don't mix the results, graphs, etc.)

Don't:
1. ... write dozens of pages, use huge letters, spread over a large number of pages. It's not the number of pages we look at, but the content. Plus, it's more difficult to handle large documents. Depending on the graphs you can fit several on one page (keep it readable though).
2. ... include code in the report (snippets are sometimes acceptable, but only when motivated)
3. ... be afraid to show initiative, present some new graph; but only if it's describing something interesting
4. ... present graphs with no explanations of the results
5. ... just say "it didn't work"; show what you did; you may be surprised. Or, at least, it gives a better impression, and lets us know you tried.
6. ... include "stories", too many theoretical aspects taken ad literam from the lectures; we are interested in YOUR insights