How to practice farming under pressure?

I've realized the higher I climb, the more pressure I face/more things are happening around the map (especially starting from high gold, where you have to participate in some fights during laning phase). I practice my csing in the practice tool before games almost every day until when I am able to score at least 85 cs in 10 minutes every time, while consistently positioning myself behind the minions and looking at the minimap. However, I feel it's not the best way to practice csing, as it does not account to the amount of pressure I face in-game. Any advice would be appreciated thanks!