Cheat Engine

[dvdrw]

Need help on hacking facebook tower defence gold

i saw many video on how to do so
i tried on the same game, but i failed

now i need help, in the value, i should put 4 byte, 8byte or double?
whats the diff?

and can any1 show me/guide me how to hack this game on facebook
apps.facebook.[com]/jiayuan/
(removed [])

this is a chinese tower defence
i tried everything
i found the value and when i change it, it wont change in the game
on the right, it is summon wave
to build building, click on bottom right first logo, and then click on most bottom to build

plz guide me