On smokers you need to understand whether you want to keep the enemy out or the enemy in. I've seen suggestions in this thread saying that you should play from spawn and smoke. This is only going to work if your team is either holding angles that benefit from smokes or if you're trying to keep the enemy team out to allow your team to rotate. Both of these require information and decision making on your part.
If you're not playing around your own smokes then your goal is to get your team into the site to retake. You will want to use a minimal amount or get your smoke timing rotation which allows you have enough time to smoke bomb and play around bomb.
If you're playing retake with your team and you get into site with your smokes intact then you're trying to eliminate angles to allow your team to take more spaces or deny vision to the enemy team to create advantageous situations for your team. If you're taking the dice route this means eliminating the uhaul and teleport angle while your team to clear showers. Then smoking box to take site control.
Also buy a shorty. There are so many opportunities for you to force an enemy player to have to take your smoke blindly.
If you're playing B, it's the same situation. Your goal should be to get your teammates into the site.
TL;DR: Do not smoke off execute. Use your smokes strategically to achieve your goals of taking space and getting your teammates into advantageous attacking positions.