In the early game I recommend that you play for level six and wait so that you have some of the items that I use in the build. The items are in no certain build order so that you can go for any of them early. If you want to survive more in the lane rush a rod of ages otherwise if you feel confident and want more damage rush a lich bane. I recommend the second big item that you want to pick up is a Rylai's Crystal Scepter so that you can stick to your opponent. If you went for the early rod of ages and you need more survivability go for the crystal scepter otherwise i recommend you build the lich bane second. Remember to buy wards and ward the river. Because of Diana's weak early game I advise you to pick up a catalyst and have it sitting in your inventory until you finish the rod of ages.

This build is very focused on sticking to your opponent. Since Diana already has so much strong potential in sticking to opponents anyway, my guide focuses on putting special emphasis on Dianas ability to secure kills and put out a lot of sustained damage. The build items like Rylai's Crystal Scepter and the Furor enchantment on her boots will make her especially sticky and constant damage from her lich bane procs, q's and her ult will have no one escaping. The build also makes her somewhat of a tank so its not too difficult to stay in fights and because of her skill set she will pass the enemy front line and go for the carries. The top lane meta includes a lot of bruisers, so that is why the recommended items to build first provide health and they keep Diana from losing trades in her weak early game.