I'm compiling a list of tips and tricks that I've had to learn whilst modifying my Jazz.
Adding keyless entry or adding additional fobs to open the car can be achieved by:
1) buying a replacement fob of ebay or your honda dealer
2) inserting the existing key for the car into the ignition
3) turning key in ignition until just before starting the engine pressing and then pressing the lock button on the new fob you are trying to program.
4) return the key to original position and repeat steps 2 and 3 two more times, if done successfully the doors should have now locked! and the new fob can be used for keyless entry! credit goes here to
Installing OEM foglights
1) Make sure you buy a kit that is complete i.e foglights, mounts, new indicator stalk (you need this as this has the foglight switch for the front), wiring loom for lights and connections for the stalk, and some other parts that I'll photograph.
2) Having assembled all you parts you'll need the right tools and a good sense of what you are doing not that the manual I had helped at all.
3) Tools needed:
PHILLIPS HEX HEAD screw driver (6mm I think will check)
12mm socket
Phillips long and short handled screwdrivers
Sharp knife or Stanley
Small Flat headed screw driver
4) As you will have to remove the steering wheel you MUST disconnect the BATTERY as we wouldn't want the air bags to go off.
Resetting the car after changes to the ABS or SRS i.e. when you disconnect any of those sensors or the lights appear on you dashboard.
(Applicable only on models with electric windows).
Simply put the key in the ignition turn to allow windows to work, wind down passenger window, then wind back up holding the button in the up position for 3 seconds when at the top and then push to put the window down on "auto" mode. If the window goes down on it's own then it's worked if not repeat and hold for longer. This resets the system and should clear all the lights, failing this re-check you connections.
Aux input for OEM intergrated Stereo This allows you to plug in toys like your MP3 Player etc.
Basically do as they say
http://www.hondafitjazz.com/audio.htm
I also salvaged a jumper from an old computer to connect pins 1+2 to enable the Aux function and used the Audio cable that normally runs from the back of the CD-ROM drive to the motherboard or sound card as this has the correct spacing and number or pins (4) to perfom the connection duties to pins 3,4, and 5.

Props to the these dudes:
http://www.hondafitjazz.com/audio.htm
Will update this thread as I go doing this at work in my spare time and will update with pics and any other new ideas please keep this thread clean and not full of silly comments.
Any other tips you have please PM me and I'll update accordingly and give props to the sender.
{PeACe}
B-boystance