How do I swap heads on a picture

[parahandy]

Using the lasso tool draw round the head you wish to use. When the circle is complete, go to edit and copy, then open the picture of the one that you wish to relace the head in and then go edit and then paste , you will be asked if you wish to paste as new image etc but go for the as a new selection or transparent selection and paste the new head into position you may have to experiment a bit here to make it look natural, it helps if both subjects are looking the same way set of shoulders etc. Both of the original pictures must be the same size when in position use the various tools to fill in the discrepancies. Like all these things it's easier to do than to explain how.
if you need further explanations let me know.you will require a steady hand .
the sample shown is untrimmed and done fairly quickly.