You don't need any fancy tools, I layered everything in a one-cup measuring cup then flipped it over.
Then topped it with spicy mayo, soy sauce and Furikake which is a Japanese condiment made with blend of sesame seeds and seaweed and spices available at most health food stores, Amazon or you can just use sesame seeds.
I'm obsessed with Trader Joe's frozen brown rice, it's a great short cut for busy weeknights and the texture is perfect. Using their rice, this came together in less than 15 minutes. If you make the rice yourself, it's best to use short grain rice like you get from most Asian restaurants, the sticky texture is perfect for this.
This would also be great with crab meat to make a more traditional California roll, or even salmon or tuna!