For anyone travelling from the north of Old Trafford I'd suggest take M602 and come off at Eccles.
You can then either park up at Ladywell tram stop (free parking) and get tram to Anchorage. 5/10 min walk from there.
Or alternatively continue in car onto Centenary/Coronet Way and park up at Media City multi storey. About £5 for parking. 10/15 min walk over Ship Canal to the ground.
If you take that route after match back to Eccles, you'll miss most of match traffic that gets snarled up around Trafford Rd heading towards M602.
Some decent drinking establishments on Media City/Lowry if you're fancying a pre match pint. Sadly Sam Platts is no longer with us.....