No special access issues
Several parking spots exist down on the roadside but from whichever one you find yourself, walk back up towards the Ogwen valley until you reach a large gulley on the left hand side. The trick is to stay to the right of the gully for as long as you can, in order to avoid the field of gorse across the other side of the hill. A vague path exists to lead the way. Once past the gorse, drop down to a gap in the wall and follow your way over towards the obvious and imposing First Bloc and on to greatness.
Note: take heed of which way you have come when you go past the wall. On the way back, remember to trend leftwards and uphill slightly in order to retrace your steps and avoid a very unpleasant walk back down.