BMW Repair: for reparing my 2001 Bmw 530i, camshaft position sensor, negative battery cable

Question
hi paul. if i try to fix the camshaft position sensor myself is there anything i have to watch out for? is it really hard to do it? will it effect anything like the engine or other things? do i have to remove the negative battery cable before doing it? how long will it take? do i have do open the whole engine or any other major things? i'm not a mechanic guy, all i try is save some $ if i can do it myself at home. can you tell me very detail step by step how to do it and send me the pics of those step. my email is lazyguy3333@yahoo.com thanks you very much for all the help.  -------------------------
Followup To
Question -
hi paul. i'm looking for the location of the intake cam sensor. is it anyway you can sent me the picture of that part's location? i been trying to get it from Expressautoparts.com/Repair yourself but i couldn't spot it. please help me . thanks
this is what it says on the dealer printed out
 66509 CHECK ENGINE LIGHT ON. FAULT 65 INTAKE CAM SENSOR SIGNAL NOT SENT. FAULTY INTAKE CAM SENSOR. I tried to type in INTAKE CAM SENSOR or CAM SENSOR or CAM POSITION SENOR but it is not found.
Answer -
If you are looking at the engine, it is on the front of the engine behind the thermostat. You'll know because it has an allen head bolt.

Answer
it is not hard at all to replace the sensor. when you get the new one match it up to the old one. you'll see the intake cam sensor on the right side of the engine at the front when you are looking at the engine. just disconnect the connector, remove the bolt holding the sensor in place and pull out the old one. make sure the o-ring comes out with the old sensor. put a new o ring on the new sensor and install the new sensor. when you are done you'll have to have the check engine light reset