It took Arvin 3 days to complete the rune formation. Within these three days, he would eat, sleep and then draw. That is all that he did. And after three days of this vicious cycle, he was finally done with rune formation.
After making a network of lines in the circle on the backside of the shield, Arvin drew different runes, and then he joined all of them in a specific manner with the help of the network of lines. Thus the rune formation was ready. But the work was done yet. One has to give power to the rune formation so that it could actually start working. Loki told him that, the more complex the rune formation is, the more power it would need to start working.
