how to modify the .h and .cc files to delay the packet

[ravi v v]

i want to reduce energy consumption but i dont no how to modify .h and .cc files.these are all the work im goi 2 do....want to delay the packet in queue i.e reduce the transmission rate to reduce power consumption without overflow occur in buffer.for that i want to assign delay values for transmission time for different packets and threshold values.im very new to ns2 so i dono how to write and implement this in .h and .cc files and also tcl scripts.pls help me with some suggestions.