I’ve been a vector artist for two years now, and after writing some tutorials on vectoring, I thought about writing some tips for those who want to take up vectoring. These may sound simple, but it’s amazing how many people ignore them or realize they are useful when it’s too late.
This article can be considered a mini-tutorial; please don't hesitate to ask if something isn't clear.

Shape layers = layers containing shapes that are created by selecting the "Shape Layers" option of the Pen Tool; they do not lose their sharp quality upon enlarging.
Raster layers = normal layers, on which brushes and paths (created with the "Paths" option of the Pen Tool) can be used together; they become pixilated upon enlarging.

1. The Pen Tool is your friend.
Everyone says you can't vector without it. I don't know whether this affirmation is true or not, but the Pen Tool is definitely very efficient and easy to use. Don't be scared by the complicated tutorials on the Internet. Keep looking until you find one that explains everything down to the smallest details or ask someone about it.

2. Choose images you like.
My advice is to choose an image you like, since you'll be looking at it a lot. If it's a request from someone and you don't really like it, find a part of it you like and concentrate on that while doing the other parts.

3. Have patience. Lots of it.
There's a saying which goes "Rome wasn’t built in a day". Vectoring is a long process; it takes up a few hours, days, weeks or even months, depending on the difficulty of the image and the spare time you have. Unless you're quick, it'll take a while to finish your vector. That's why you'd better get a cup of coffee, a soft pillow for your bottom and lots of patience. You're gonna need them.

4. Start easy, work your way up to difficult.
Most artists weren't born talented at vectoring. It's not shameful to practice or start with easy images. For example, if you're an absolute n00b and barely found out where the Pen Tool is, the result of a battle between you and a black & white manga scan is obvious. So instead of taking on a "challenge", settle for a colored, good quality image for starters. If you fail at your first attempt, try again. If you fail at a difficult scan, things won't look too bright for your self esteem.

(Left: artwork by REI, Right: image from "Fairy Cube" manga)

5. Arrange your workspace to fit your needs.
When you open your graphics editing program for the first time, there are a lot of small windows with various options on the screen. Sure, they're useful, but they're also shrinking the "free" workspace considerably. Since at first you don't know which ones you'll need more often, you'll have to practice a while. Then, you can eliminate the windows you don't need or use frequently. For example, I only have the "Layers" and "Tools" windows.

6. Enlarge the image as much as you can.
It's always easier to work with a larger canvas because you can shrink the vector however you want. This is useful for vectors with a lot of raster layers. As for shape layers, the outlines will get thicker if you enlarge them, so that might also be a disadvantage if you want to use it as a close-up (thinner lines look more delicate).

7. Zoom in at least by 200%.
You found an image you want to vector and opened it in your editor. The best way to obtain precise lines is to zoom it at least by 200%. Your lines might look huge, but when you switch back to 100% they will look more delicate and accurate. You'll find this method very useful when vectoring images with small details, like jewelry or eyes.

8. Name and group your layers properly.
Alright then, this is particularly useful when you've got a lot of layers to work with. For example, if you're vectoring a character, you have separate areas: face, arms, legs etc. Putting the respective layers in groups makes everything look tidier and it helps a lot when you need to find a specific layer. Furthermore, groups can be hidden and displayed, so you won't have to scroll down the long list of layers until you find what you're looking for; instead, just open the group which contains it.

9. Use as few raster layers as possible.
One of the differences between shape and raster layers is that raster layers become blurry and pixilated when enlarged, while shape layers maintain their quality however you change their size. If you plan on making a real vector, shape layers are highly recommended. Sometimes, raster layers can be used for adding glows to the image and, since they are already blurred, won't look bad.

10. Use gradients for more complex shading.
OK, so now you got the basics and made a vector with base coloring, shading and/or highlights. But you're not satisfied with what you've got and you feel like something's missing. What is it? The shading – it bugs you. You've seen vectors with colors in gradients and liked them. Why? Well, using gradients for shading makes the vector look more complex, as opposed to the traditional cel shading, which can sometimes look cartoonish.
In Photoshop CS2: for gradient shading, right-click on your layer, go to "Blending Options...", then "Gradient Overlay" and select your gradient from the list (or make your own).

(Vector by Sweetdevil, original image from "Beast Master" manga)

11. Ask for assistance if you encounter a problem.
No one will chop your head off if you ask for help. They might even feel proud that you asked them. I suggest asking experimented vector artists, since they tend to know better what they're talking about. If someone's rude, don't give up! Contact someone else.
Looking for online tutorials can be helpful, but some people don't know how to or can't explain things clearly. If you know someone who can show you how to vector in person or in real time (through instant messages), don't hesitate to learn from them. It's the easiest way and you can bug them until you know you got it ^_^

12. Improvise!
This is when you start to need some experience in vectoring or drawing, since improvising makes great use of your imagination. You start off with just vectoring an image, following the lines the artist drew. But with time you aren't satisfied with only copying what someone else drew, you want to enhance that image! Whether it's adding a bracelet or changing some hair locks, improvisation is appreciated and welcome – think of a breath of fresh air on a hot day. It also shows you now your way around your program and can exploit it as you desire. This way you can modify parts you do not like and end up with something that fits your taste.

13. Find your style.
You're a relatively experienced vector artist now. You've vectored a lot of images and know what type of artwork you like. Vector by vector, you'll start noticing a pattern of changes you bring to the original artwork. This is your style. If you've looked at vectors from different artists before, you'll know what I mean. One makes an abstract background, another uses thin outlines etc.
In my case, it's the eyes. I can't stand simple eyes, so I enhance them as much as I can, adding lots of details like shines and shadows.

I hope you found this article useful and will benefit from it, if you decide to explore the world of vectoring. It's very important to respect these tips, since they will help you on your way to perfecting your artwork. Everything here is written from personal experience.
Please share your opinions, ideas and tips here. Thank you for reading, and see you next time! ^_^

All vectors featured in this article are done by Olivia a.k.a. Sweetdevil. The anime/manga series represented are copyrighted to the original owners.