This recipe is one of the easiest and best margaritas I think I make. I think you will find this is a good all around margarita. Also I never add salt as I have noticed that it can take away from the freshness of the cocktail.
3oz Patron Silver Tequila (Or opt for an Anejo Tequila)
1.5oz Grand Marnier
3oz Blood Orange Juice (Best if fresh)
1.5oz Lime Juice (Best if fresh)
1oz Agave Syrup
Mix water and agave, then mix with the rest of the ingredients in a shaker with some ice. Shake and strain over a tall glass with ice. Garnish with a blood orage slice.