How do I call async methods in asp.net C# 4.0?

I'm aware that with .net 4.5 there is the await, async keywords that allows for easy calling of async methods. I 'm currently studying how to make async calls in C# 4.0. An example I want to is to make an async call where the datagrid is being databind.
If you could provide me some links or sample codes I would really appreciate it.
Thank you++ :D
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