If you are creating a standard granny square blanket and dreading finishing it off, have a go at crocheting the squares together.  It creates a really lovely, neat finish with ridges on one side and completely flat on the other.

Because of the nature of crocheting squares together, you will need to choose the colour of yarn carefully as it will be a feature on one side.  If you want the sewing up to merge in with the granny squares then finish the last round of every square in same colour and your crocheting together will be almost invisible.