I've seen quite a few blogs on how to edit your profile, but none on how to design your profile in an appealing way. Here are a few tips I believe should be followed (assuming you already know how to edit your profile):

Image Sizing:
I've noticed that many users using rather obtuse images, some as large as 1000 for one of its dimensions. Design wise, pretty much anything that stretches beyond the DSi's 240px width is a no no. If you don't have access to an image editor (with GIMP being among the best that are free), make sure the images you use fall below the previously mentioned screen width.

Another useful tip that I was given (from Gleeok) is that it's best to center images that are under 210px in width, as it fits well that way.

Colors:
Here's a little art lesson for you guys: colors generally look great with colors opposite them, and directly next to them, on the
color wheel.

For example, purple brings out the essence of yellow, and causes less eye pain when viewing it, like this. In any other instance, it's best to avoid yellow. I've also found that with the use of neighboring colors, like light blue and greenish colors, for the background and text respectively, work well together too.

Borders:
Depending on the background of your TDs, changing the the color to a color perpendicular to it on the color wheel seems to fit well. For example, on my profile, I have the background of my TDs set to a light blue, and my borders set to gold (basically yellow). I believe following this tip can greatly improve one's profile. Another thing to consider is the type of border to use, which includes grooved, solid and dashed among others. Which type looks best is in the eye of the beholder, I suppose. Go with what you like.

Backgrounds:
Several users use backgrounds well (both comment box and page backgrounds). For the comment box background, make sure any image you use is rather small, around 200px in width or less, so that it fits the box neatly. For the actual page's background, having it fit well with your DIVs and TDs visually is always a nice aspect to have (of course, mine is a stained glass rainbow background image. )

There is probably a lot more that could be said in the way of design tips, but I'd say these are the basics that will help some of you who are unsure of how to actually design your profile.

Happy trails,
Skittles.

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Always be sure to proofread to make sure you didn't any words out.

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