This was a fun one. The plaid is actually freehanded, which took way longer than I'll ever admit. On the other two nails, I did a side-swept look that was inspired by the queen Sarah from Chalkboard Nails. I ended up making vertical sweeps too.
China Glaze - Bahamian Escape (light blue)
essie - shelter island (slightly darker blue)
essie - make some noise (medium blue)
Note: make some noise actually stains a lot. I don't recommend this if you don't know how to get rid of stains on fingernails and cuticles (or just don't want that kind of mess).