On a bamboo sushi mat*, place 1 nori sheet*. Using a rice spreader, or your wet fingertips, spread a 1/4-inch-thick layer (0.5cm) of rice over the sheet, leaving a 1.5 inch (4cm) margin on the top border.
Sprinkle the rice with sesame seeds, then flip the nori over, as shown in the video (this way, the rice will be on the outside). Arrange the salmon, cucumber and chives starting at about 1 inch (2.5cm) from the bottom border.
Using the bamboo mat, start rolling towards the top border. Once you get to it, moisten with a bit of water, then press to seal.
Place the sushi roll on a clean chopping board* and, using a very sharp knife, slice it into 8 pieces.
Repeat this process with the remaining nori and fillings.
Serve with soy sauce, wasabi and pickled ginger, if desired.
Video
Notes
Don't forget to wrap the bamboo mat* in cling film* so you won't have rice getting between the bamboo sticks. This way, you won't even have to clean it afterward because it doesn't get in direct contact with any of the ingredients.
When rolling the mat, apply some pressure to make sure it's tight and the filling won't come off. More on this at Tip #7.
To cut the rolls easily, use a very sharp knife* and moist it with a wet paper towel, so the rice won't stick to it. More on this at Tip #8.