Ok now I've created Machinima since 2007 so I kinda have a knowledge on what to do now 
Here are my beginners tips and tricks :1. Puchase The Sims 2 - Obvisously you need to have a copy of The Sims 2. Personaly I don't think you need all the extension packs. I'd say you'd most likely need uni for the band equipment. Nightlife for dates, cars, interations. Pets for obviously the animals. Seasons for the weather change, possibly the gardening and fishing. Bon Voyage for the beaches and awsome settings. I personaly don't think you need Open for business, Free time or Apartment life, but that is just me everyone is different. Just always read up on each extension pack before purchasing.
2. Play the game! - Play the game till you feel comfortable, understand all the controls and looked at the animations carefully. Don't just rush into it! Many have made that mistake.
3. Download hacks - There is many many hacks out there! But the two main ones you will need are the
Camera mod and
Light mod. Once you have made a few films then decide to use pose and animation boxes...
Full list here.
4. Practise makes perfect - Don't create a video quite just yet... experiment with the two mods and film little things... then edit them... it's basicly practise.
5. Start downloading CC - CC stand for custom content which is basicly adding new clothes, hair and items into your game. Monthly updates on downloads are provided on the forums. But you can also go to these two sites -
Mod The Sims,
The Sims resource. Basicly with these two sites you type in the search bar what you need, for example Hats. If the those two sites don't have what you want then post into the
WCIF? section on the forums.
6. Create sims - Have a little go at making a wide range of sims to get some practise. If you work at it long enough you can create beautiful sims! They won't turn out perfect to start off. but thats normal... so keep it up

you will get beter along the way.
7. Learn to build sets - Make sure you have lots of clutter! Like for example in a kitchen would have spice racks, kettles ect. Just basicly find items for you yourself would have in your home ect.
8. Start writing! - The best way to plan out a video is write up a plan... that way you know what your doing
9. Get filming! - Now you've done all those steps it's time to create your first film! Good luck
SimqueenPlayer3's tips1. Have good graphics - turn off the sound and put the display settings on max.
2. Good editor - I good video editor is great but don't use too much effects or it will not look as good.
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