What's an effective method to strain liquids?
Cheese cloth is easy to find and does a great job when we make horchata.

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I use a regular mesh strainer like the one below, and I line it with a few layers of cheese cloth.  Depending on your colander's design, it might work too.

The number of layers depends on what your straining, and how loose the cheesecloth is.  I use it more often to make mascarpone cheese and I typically use 3 or 4 layers.  

I set the strainer over a large bowl and load the strainer and cheese cloth with as much unstrained liquid as it will take.  Something like horchata shouldn't take too long, a few minutes maybe.  When I make mascarpone I set the strainer (in its bowl) in the refrigerator overnight.