My daughter took the test for SGHS last year and is due to start in Sept this year.
Last year(Oct and Nov) the tests for out of area pupils were arranged by North Yorkshire County Council and held at Rendevous hotel in Skipton.
Both the girls(SGHS) and boys for Ermysteds sat the same tests together.
Both tests consisted of Nfer Verbal and Non Verbal tests(multiple choice format), also there was a practice test about a week before the first of the two tests.
Are you in area? If so your child will take the tests at his current primary school, unless you opt out of selection.
For more info contact Craven Education, Skipton. As you must apply before a certain date for out of area(last year it was late September I think)
Hope this is of some help.