Have you ever watched any one else's presentation. Did it look worthy for your time ? How many times you actually listened ? Did the PPT reading is easy than hearing attentively what presenter is speaking ? Your answers are mixed, right. That's how a PPT is - a mix few thoughts.
Every time you gave a presentation possibly all the times you have to submit the PPT somewhere else after the presentation. So it is expected from you that you made the PPT from a documentation angle also. So the first point is don't make it too short that the context won't be there for second time readers. Including only bullets are completely fine but when doing so give a short description (of what the bullets are) below the heading.
Every time I make a PPT the first thing I do is drawing the whole design and animations in my brain. As Einstein once said possibility is not the mother of inventions, Imagination is. This habit has been helping since ages. Even now when I make a app or website, I design the wireframes first with a simple pen and paper. People say thinking animations and implementing them is too difficulty. Yes it is - it is difficult that's why it will make you stand out.
Trust me when I say this - Times New Roman and other fonts that your prof suggested are as outdated as your ex. Follow great designers - see good presentations on Pinterest or Behance or Twitter - Crave for minimalism with your own rules - experiment with new fonts and colors. I used the font LATO when every one in my class using the safe bet Calibri or times New roman and you already guessed which one is better.
It does not always happens that I came with a design From start to finish. I also keep my creativity alive through inspirations. I see them - observe the designer's thought process and then mold it to my likings. Below giving some ways you can take inspirations from. Pitch - Prezis - 24Slides
I have seen a lot of people using Canva for making PPTs. Listen it and register it - Canva is actually killing your creativity. Don't take me wrong Canva is great tool for other stuffs but just not for PPTs. Always use PowerPoint.
Don't hesitate use multiple file types. There are times when I download a element from FreePik just because I love the background, then import it to Illustrator to remove the background and elements and import them individually to PowerPoint. Talking about multiple file types, I personally don't use sounds in a PPT, but it's just fine you like them. Use various tools - Find new websites - try different things and rock that Presentation.