Put the tip of the injector in the gate/sprue/injection port, raise the vent-side of the mold (leave the sprue/runner-corner of the mold on the table)...this makes the vents the highest part of the mold...inject S-L-O-W. Let the plastic "flood" the interior of the mold, like a boat taking-on water. This helps prevent trapping air in the details of the cavity.