Grafton is easily reached from Junction 1 (Cadnam) of the M27, the most direct route is to leave the M27 & travel through Lyndhurst & Brockenhurst. However, at peak tourist times the traffic in Lyndhurst is very heavy. An alternative is to leave the M27 at Junction 2 & follow the Brown Monument signs for Beaulieu (ignore signs to Beaulieu Station). Go right through Beaulieu village & at the T junction on the far side of the village you will find signs for Lymington.
This takes you past Hatchets Pond, on your right hand side, a popular picnic & fishing spot. Good for seeing horses, donkeys, ducks & swans. They seem to congregate there.
Please take care driving through the Forest, the animals have right of way & they seem to know it too!!