Great idea ^. I doubt any of these are unique to me but they're very useful tips so worth sharing...
Filming a TV
This worked great for me: FPS of 30, shutter speed of 1/30.
Filming a laptop screen
This worked great for me: FPS of 30, shutter speed of 1/60 [but you need to get the screen angle right too - to avoid flicker].
Filming a cell phone screen
Have not managed to get this without flicker. Advice welcome.
Be wary filming with your talent beside a large window
Easy to get blown out shots. Pick a time of day where the sun is going down, golden hour is good.
Audio: get a solid reference audio track too, has saved my bacon a few times
Audio: always have someone constantly checking your recording live with headphones
... have had a few tacks ruined due to interference from cables (eg audio cable near a power cable), cell phones
Audio: have everyone on set switch off their cell phones
... again, a few of my audio recordings have been ruined by cell phone interference
Audio: if you're filming in a location with a fridge/freezer, ask if you can turn it off
... be aware of the food inside and don't leave it off for too long
Audio: most novice film makers concentrate on getting the visuals right; don't make the same mistake - the audio is as important
Visuals: buy a field monitor as soon as you can, they're invaluable
Visuals: get your focus right, always punch in using the camera's zoom to check focus - eye lashes or eye brows are a great check point
Visuals: make sure your scene is level
... I have had a number of shots ruined due to the level being off - even just slightly. The scene sure looked level at the time... In post on a 30" screen, it proved not to be! Advice welcome!
Talent and crew: Treat everyone well and with respect
Talent and crew: Treat them really well and look after them. Make sure they have good food and lots of liquids available. This goes triply so if they're working for free.
Talent and crew: don't get anyone hurt! Doing stunts, fight scenes etc. Don't take risks. Learn how the pros do it and ideally get a pro on set. A film is short term, health is needed for the long term. And no one wants a law suit.
Always keep multiple backups of your work and label each drive
... I have MASTER, BK#1, BK#2 etc
USB 3 is your friend. It's 10x faster than USB 2. Buy USB 3 compatible computers and external drives. What's your card reader? Make sure it's USB 3 too! Lacking enough ports - get a USB 3 hub (I have 2x USB 3 hubs)
Post-production: How's your Premier Pro or Final Cut set-up? You are using multiple drives right? And have them set up in your editor's settings. If you're just using your PC's drive, you're going to pay for it dearly with poor performance. My Premier is set-up with 3 external hard drives: Source, Output and Caches. My PC's drive only has the editor on it.
Story, story, story: if you're making a short or feature don't bore us. Give us something that keeps us riveted. So concentrate on the story - which includes great characters and good dialogue.
... You'll find lots of advice on that topic in the links on my sig.