How to Design a Vector Logo using Illustrator
This tutorial will show you how to design your own Logo in vector format using Illustrator's Appearance Panel.
Step 1. From text to outlines or Vector
Type out the text for your company logo in your preferred font. I chose to use 'Century Gothic', simply because it's nice simple font and it will also be easier to edit the characters because it is doesn't have any serifs or other fancy effects. I sized my example to 50pts.
Select the text and from the menu select TYPE>CREATE OUTLINES.
Now your typeface will no longer be editable as a typeface and is now effectively a series of vector images, just like any other standard vector image. But obviously we're going to work on it further and show you a few simple techniques to help you produce your own unique vector logo design.
Step 2. Making your logo Unique
Now the text has been vectored you can easily play around with the lettering to try and produce something a little more imaginative and make your logo unique. I decided to place my text onto 2 lines and I'm going to customize it a little bit by curving the end of the letter 'L' so it fits in better with the 'o' next to it.
Using the 'Direct Selection Tool' 
select the lower right side of the 'L' and while holding down the SHIFT key drag across until it overlaps the 'o' next to it.
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Select the 'o' and from the menu go to OBJECT>PATH>OFFSET PATH and select a value that looks about right, I used 0.8mm.
With these 2 offset lines still selected also select the 'L' as above, go to the PATHFINDER PANEL and choose DIVIDE.
This will divide all the selected elements into separate segments. Using the 'Direct Selection Tool' select the pieces that need to be deleted and you should be left with something similar to this.
Try experimenting with the lettering, repositioning the letters, resizing, merging as sometimes just playing around can usually produce interesting and unique results.
Step 3. Applying the Effects
Once you're happy with your logo design you can now customize it further using lots of different methods. But we're going to use one of my favourite techniques which is using the APPEARANCE PANEL. From the Menu WINDOW>APPEARANCE.
With your design selected click on ADD NEW FILL from the bottom of the APPEARANCE PANEL and choose a colour. It doesn't really too which colour you select as you can easily change this afterwards.
Repeat this step again and select white from the colour swatch and then go to EFFECTS and choose PATH>OFFSET PATH and set the value to 2mm.
Drag the white layer onto the duplicate icon. From the bottom fill layer change the colour to a light grey, then from effects choose OFFSET and select 1mm.
You should now end up with something like this below.
Now to achieve the 3D effect. Select the bottom grey fill layer from the APPEARANCE PANEL and drag onto the Duplicate icon again. Now select the bottom grey fill layer and from EFFECTS go to DISTORT & TRANSFORM > TRANSFORM and change the values for the horizontal and vertical from the MOVE slider to 1mm.
Repeat the last step but make the colour a darker grey or black and make the TRANSFORM settings 0.5mm instead of 1mm. This gives a slight shadow effect. You could if you prefer use the DROP SHADOW effect instead.
You might like to add a background to enhance the effect.
The great thing about the using the Appearance Panel is that you can easily go back and change any of the settings to experiment.
Once you're satisfied with the final result save this as your master copy. The only problem you will now find is that when you resize your logo the effects created in the Appearance Panel will remain at the same sizes, such as the OFFSET and TRANSFORM settings. Try it and you'll see what I mean.
The way around this is to select the whole logo and from the OBJECT menu select EXPAND APPEARANCE. This will get rid of the editable Appearance layers but then you will also be able to scale it up or down and the whole image will appear the unchanged, no matter how large you scale it up. Perfect for large banners, vehicle graphics and signage etc.
That's basically it but you can try experimenting with the Appearance Panel settings to achieve lots of interesting effects.
It's even possible to use the Appearance Panel on editable text without having to expand it. That way if your company name changes slightly all you have to do is edit the text and all the effects will remain unchanged.