When you press the lid with a sponge the detergent automatically goes to your sponge and you can clean the dishes. The only extra thing you need is the device extracted from a liquid soap dispenser. Find the cheapest one in your local market, cut the cap out, and use it.
It's an excellent little project, a userul device, and a great gift.
Watch the video for an explanation.
Parts of the liquid soap bottle dispenser after I cut the cap. Be careful, use plier or a dremel.
The author marked this model as their own original creation.