Spread the bamboo mat with a part of plastic wrap on top (this way the clean-up will be easier and stop the rice from gluing (sticking) to the bamboo).
Fold up the nori sheets in fractions and divide them with a pair of scissors.
Put half of the nori towards the base (bottom)of the mat.
Gently wet your hands and acquire approximately 3/4 cup of cooked rice. (You can plunge your hands into vinegar water to stop them from sticking together.) Lightly scattered the rice out to the fringes in a thin even order. Do not implement too much pressure, or the rice will be squishy (mushy).
Place the rice and nori over so that the rice is at the base and the nori is positioned at the top.
Put the cucumber, shrimp, and avocado above the nori. Remember not to put in too many fillings (stuffing) or your roll will not close well.
Set the thumbs beneath the bamboo mat and raise the edge up and above the filling.
Scroll the bamboo mat away from you and put in some pressure to make it tighter. Just keep rolling till the ends make contact with each other.
Pull the bamboo mat, and spray the tobiko above the roll.
Set the plastic wrap on top, and shroud (fold) it with the sushi mat. Squeeze lightly to clamp (press) the tobiko over the roll.
Extract the bamboo mat while saving the plastic wrap for later use. Slash the roll into 8 bite-size portions. Pull the plastic wrap from every portion. Finally, now you can feast!