You can't really go wrong with a half moon mani because it's such a classic, and this colour combo is one of my faves. The red is Asiatique by MAC & the nude is Nude Beige by Models Own. I did it by starting with the red, and, once they were dry, (I may have sneaky cheated & painted a coat of Seche Vite on to help them along), I used french tip guide strips (you can pick these up dead cheap, I think I got mine in Poundland!) to tape off the area that I wanted to paint nude & just painted them below the guide strip. Once the nude is dry (or as dry as your patience will let you- although don't try & take them off too early because it will be sticky & smudge), I finished with a glossy top coat, Seche Vite is my favourite because it dries so quickly & leaves such a glossy finish.
It's a really easy way to get a nice smooth line, although I have seen ring reinforcement stickers used as well which is quite clever if you can't get your hands on some guide strips.