have you got pastry cutters?
practice size by cutting one bigger than the hole for the pie, see if fits well, to be the base of the pie. then lid must be about same size as the hole.
if no pastry cutters use a thin rimmed glass or mug, and a smaller one for the lid.
you should roll the pastry as thinly as you can really as a higher proportion of mince meat to pastry makes it extra yummy.
brush the pastry edges with milk to help seal after you attache lid to base of pastry case. also you can use a little beaten egg i think. remember to prick with a fork. sprinkling a little caster sugar on the pies is good too.