It'll help if you had a specific question regarding proxies.
Here are a few notes on proxies -
1) Proxies allow you to work with a lower resolution media of the original, full resolution media
2) The proxy is a real file that is created. Select a footage item in the Project Panel and goto File>Create Proxy to create a proxy.
3) Ensure that your proxy file shares the exact same aspect ratio as your full resolution file.
4) You can also create a proxy of composition
5) Once a proxy is in place, you can switch between the proxy and the full resolution version by clicking on a square checkbow, to the left of the footage item
6) In the Render Settings dialog, ensure that the proxies settings for render are what you want. Occasionally, proxies are desired for preview renders and always the full resolution media is required for a final render.
Need more? Here's Serge's COW Tutorial on working with proxies -
Using Post Render Actions to Pre-render elements and create proxies.
HTH
RoRK
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