Clean the jar and weight thoroughly - I recommend sterilizing them in the oven just to be safe - remember to let them cool afterwards.
Place everything in the jar, putting the largest cucumbers horizontally at the top to prevent others from surfacing the water. Leave enough space for air at the top.
Add water and salt - a tsp of salt for every glass of water. Use clean water preferably filtered or mineral.
Wait two weeks, opening occasionally to prevent pressure build up.