The valve cover and the head? Yes there is a gasket if so and its a valve cover / rocker cover gasket. Its a 2 peice deal and simple to put on. Over time and with heat they turn from soft rubber to plastic, and when this happens they dont seal and tend to crack, causeing leaks.
All you need is a 10mm and pliers for the hose clamp and some rtv. Take out the plug wires, and remove the breather tube. Remove all the 10mm bolts (can leave the wire holder ones in) including the center ones. Take the cover off and remove the gasket. Clean the rtv off in the half circles on the front and back of the head. I apply some oil to the gasket (stick your finger in a pool in the head or use new oil), and rub it all over then place it into the valve cover. Apply rtv to the half circles (like you just cleaned) on the new gasket making sure to get some in the corners Place back on the head making sure the lobes of half circles are sitting in there right.
Then tighten it down, with light to moderate torque, you could torque them to spec but I dont. But being your first time you may wat to do that hehe.
reattach the wires and tube and its good. Start it up and check for leaks to double check.
Um and dont get anything in the exposed head
Oh and if this isnt it please be more specific.