To calculate the stress σ in the "y" direction, the equation σ=P/A is applied. The user computes the force as -0.8*10^6 N and subsequently calculates stress as -100*10^6 Pa. Suggestions include ensuring correct unit handling throughout the calculations and avoiding unnecessary conversions to simplify the process. Additionally, a shortcut is mentioned where dividing the distributed load by the width can yield the stress directly. The discussion emphasizes accuracy in calculations and unit management for effective results.