Kaaskiller did a good job at explaining CheatEngine, The method he explains is no different than whats listed here. Except that you don't need to go searching for the addresses. Instead of the address that he lists for EXP you should use 01AD1D9C.
And from there im confident that you can figure the rest of the things for yourself. Note that if you want to complete say a headshot challenge and it needs 250 kills you should change your value to 249 instead of 250.
The Following User Says Thank You to Aphicis For This Useful Post:
Take Good Notes that IWnet have been Patched along with VAC2 that now Detect Any Coding Modification in the Game. So I guess that If you do that you change the Code and Have the chance to be flagged for Hacking. Take notes that once your Flagged it can takes about 5-8 days to get VAC Banned. Use it Carefully!
I tried to find the Adress for respawning sofar iam unable to find the addres for respawning.. So as far as i tried a respawn hack in S&D isn't going to work! Well, maybe with a packet editor but i couldn't find it with cheat engine!