First, are the bamboo leaves you used still on the surface of the soil? If they are you can rake them up and form a heap with them, get all the spent
coffee grounds or spent tea leaves you can get your hands on and add those to the center of the heap.
If you have any leafy green material that too can go into the center of the heap. The method I use now is to build the heap, then I pull out the center down to about half way to the bottom, I put in my coffee grounds and greens then put the material I removed from the heap to make the hole back and at this point I
water the heap until it starts leaking water out the bottom. Now you just walk away for a week or two. The coffee grounds and greens will cause heat to build up in the center of the heap and you are on your way to having great compost.
I don't turn heaps unless I just have to. I use a 3/4 ID piece of pipe to punch holes all the way around to the ground so air can get in, but I don't do that until I see the heap start to settle. I also don't compact the materials I am putting into the heap, any settling they do is by gravity only.
I get finished compost in under 6 months with this method, your mileage may vary because it is very depended upon what materials go into the heap.
The materials I use are: dried leaves, grass clippings, kitchen wastes that don't go to the hogs, dog
poop, hog poop, small branches that are cut into 10 cm lengths (these are smaller than my little finger),
cardboard, paper products that don't have a plastic coating,
wood ashes, all plant trimmings.
If it wasn't made by man, then it will compost. I have in the past even composted disposable diapers ( you do have to remove the plastic outer covering).
The only other way to make bamboo leaves good for soil is to burn them into a light charcoal but this requires a barrel with a lid so you can do it right and it really is my last ditch method.