While traditionally, the Blue Hawaiian is a rum drink, using tequila isn't that uncommon, either. This is my usual go-to for the tequila version.

Start by rimming your rocks glass with roasted coconut shavings
Then in a tin, mix:
1.5oz Blanco tequila
0.75oz Blue Curacao
2oz Pineapple juice
1oz Creme of Coconut
Add some ice, shake vigorously for 15-20 seconds, then open pour into the prepared glass.