No worries.
Replacing the light bulb is easy.
Just pop the hood and check out the back of the headlight assembly. Your headlights may or may not have a rear cover. if it does, it's easy enough to remove; just look for a couple of metal retaining clips on the top side.
Once the cover is off, you will have exposed the back of the reflector and the wiring. There will be 2 wiring connectors: 1 for the main headlight bulb and another for the foglight. Pull off the plug for the headlight and then release the metal wire that holds the bulb in place. ***Note: this step is for European spec headlights (1-pc glass on the front); if your car has North American headlights (the front lens is a combination of plastic and glass) the I think it's actually a plastic collar that you have to turn to release the bulb.***
Afer you've done all of that, all you have to do is pull the bulb out.
To install a new bulb, just follow the above steps in reverse. the bulb can only fit in one way and the plug that goes on the back of the light bulb will only fit one way as well.
Make sure that you don't touch the glass part of the bulb with your skin. The bulbs get quite hot and the oils from your skin will create hot-spots on the glass thereby shortening the life of the bulb. If you do happen to accidentally touch the glass, you can clean it with alcohol; but it's just best to avoid contact to begin with.
Good luck!
BTW, if you need 190E specific information, try
www.190revolution.net. It's a site dedicated to the 190E.