Peel, deseed and slice the cucumber. Thinly slice the onions into half moons. Place the cucumbers and onions into a tight mesh strainer over a bowl and sprinkle with salt. Toss around to evenly coat with salt. Let sit and drain for 20 minutes.
In the meantime, chop the dill.
In the bottom of your serving bowl, mix together the vinegar and sugar.
Press out any excess water and add cucumbers and onions to the bowl. Toss around. Add the chopped dill and mix well. Serve immediately and enjoy!