I always wanted to keep playing dokuro but every time I start it again I don't know what I'm doing.
That is one thing they are bad about. They'll introduce a new chalk mechanic, use it for a stage or 2, and then it will disappear for several stages. After not using the water power for 4 or 5 stages I couldn't figure out how to progress in a level of the last stage and it called for the water power.
The White chalk power is only used when you see a short, hanging, white cable not attached to anything. Either draw a line with your finger from the hanging cable to a platform (or more often) a rolling boulder. It has to be directly below the cable within 10 or 20 degrees. It is the first power you get and it is used the least.
The Red chalk power is a floating line of flammable red powder. Draw a line with your finger from a heat source (flaming enemy, torch, open flame) to unlit torches (lit torches kill ghosts and stop suits of armor from moving) or explosive barrels (which destroy weakened barriers and wooden crates).
The Blue chalk power allows you to spawn water. Draw a horizontal line from one vertical wall to the other with your finger and where you drew is the water line. Any wooden objects will sink halfway into the water and then float, allowing you to create bridges across gaps that you don't have enough crates to fill.
Sometimes maneuvering around requires switching between hero and skeleton form. For instance the hero is both wider and taller so he can't fit through some gaps that the skeleton can. Both the hero and skeleton will drown in 2 or 3 seconds of being submerged in water, but because the hero is taller he can perform actions in standing water that would kill the skeleton. Sometimes you need water that high in order to float objects high enough that you can move them.
Hero form is given a rapier which can kill all enemies except ghosts. Skeleton form is given a weapon which can't kill, but will knock most enemies back a great distance. Sometimes this is used to get enemies to trigger traps that will kill you/the princess and sometimes it is preferable to knock the enemies off ledge rather than kill them. Some enemies when killed do not come back, but if they are spawned from a portal, once they are killed another will spawn in 10-15 seconds. If you knocked them off the ledge and out of the way instead of killing them, another won't spawn.
Another core mechanic that comes into play is stacked objects. If two objects are stacked on top of each other with their edges lined up, you can't push the top object off.
#
#
But if you slide another object that is the same height as the bottom object next to it (or move it over to a ledge that is the same height)
#
##
You can either push the top object off to create a row of 3, ###, or slide the top crate over to the second object, by pulling it, then jumping to the other side and pushing it the rest of the way.
Another thing you'll do a lot is push crates off a ledge onto a crate that is below. If you offset the lower crate position so that the crate that lands won't line up their edges, then you'll be able to push the top crate off whenever you want.
#
#
You can also offset stacks by pushing a crate stack that is too tall into a low hanging ceiling and the lower crate will continue to move forward, but the top will not. Or straighten an offset stack by pushing a stack of crates into a vertical wall.
Another puzzle element is inverting gravity. At fixed points you can press circle and flip gravity 180 degrees (the princess does not suffer fall damage when shifting gravity). This causes all movable objects and enemies also to flip and start walking on the ceiling. Sometimes when you can't make it through by pushing blocks into gaps on the floor, you can make progress on the ceiling.
One common gravity puzzle is a collection of blocks in an area where you can shift gravity back and forth. These are like those sliding tile puzzle games in which there is one open gap and you have to slide the tiles around to form a picture with an added wrinkle. In this gravity puzzle, the floor and the ceiling are a different shape. The ceiling may be flat, and the floor might have a few shallow pits. You invert gravity, move what crates you can on the ceiling, then when you return gravity to normal you can make new crates moves on the floor. Those moves allow you to make new crate moves once you invert gravity again, etc. By shifting gravity back and forth, moving crates each time, you can now, for instance, slide an explosive barrel that was previously under 2 crates, next to a breakable wall.
There are also videos on youtube for all the levels if you get stuck.
[...] but every time I start it again I don't know what I'm doing.
#promnight