Start by washing the cucumbers thoroughly. Slice them into thin rounds or half-moons, depending on your preference.
In a mixing bowl, combine the sliced cucumbers and salt. Toss well to ensure all the cucumbers are coated in salt. Let them sit for about 5 minutes to draw out excess moisture.
In another bowl, mix the white vinegar, water, sugar, sesame oil, red pepper flakes (if using), minced garlic, and grated ginger (if using). Stir until the sugar is dissolved.
After 5 minutes, drain the cucumbers and gently pat them dry with a paper towel.
Add the drained cucumbers to the vinegar mixture. Toss to coat the cucumbers evenly.
Transfer the pickled cucumbers into a jar with a lid. Make sure they are submerged in the liquid.
Seal the jar and let it sit at room temperature for about 10 minutes to allow the flavors to meld, or refrigerate for longer (ideally a few hours for best flavor).