tip 1 - take out of fridge in the morning, first thing, else when you come to cook it the first x mins are spent just warming it up.
tip 2 - remember that resting time is very important. Allow about 20 mins to rest before carving. In this 20 mins the beef will conitue to cook. Therefore it can be a little redder when you take it out and won't be quite so red after resting time.
tip 3 - push knife in to make holes and push in slivers of garlic
tip 4 - serve with piping hot thick rich gravy. Whether it's under or over cooked this will help!
tip 4 - serve with greens, sugared/buttered carrots, parsnips, roast potatoes & yorkshire puds *(buy em already made - Anutie Bessies) and horseraddish sauce
For potatoes - boil for as long as you dare, take them out before they start to break up. Give them an hour to cook, around the meat. Then when meat is resting put potatoes in a new baking tray so they are dry and finish them off, this ensures a crispy potato.