How to make a simple Do-It-Yourself foam letter sign

Here are a few easy-to-follow steps for making a foam letter sign.
Before you start, here are some basic descriptions to help you plan for what you need. You may want to print this out and save this or forward it to someone looking for guidelines.

Contents:
What are foam letters?
Where can I order foam letters?
How can I find the cost?
How large do the letters need to be?

• available space (for your sign)
• how far does the sign need to be readable?
• aesthetics

What do I need to have to make this turn out well?
Using the yardstick
Before you glue or cement anything in place
You're almost there!

What are foam letters?

By "foam', I refer to the dimensionally stable extruded plastic "foam", which is cut into letters usually
from a 4x8-foot master sheet. The sheets are usually available in 1/2", " and 1-1/2" thickness, so for the sake of this brief article, I'll refer to 1" thick letters when I mention foam letters.
Foam letters are weather-resistant initially, but for outdoor use and installation, I recommend ordering painted letters or painting them yourself.

Where can I order foam letters?

Here are a couple of different types of letters for online ordering, or visit craft stores, which usually do not offer the ability to get your own typestyle in almost any size you need. And speaking of sizes, how do you know which size to use?

How can I determine the project cost?

Use this form; it's for concrete casting (surprise! Something else you can do with foam letters!)
Select single-use foam and fill in the details!

How large do the letters need to be?

The best, or optimal size for your project is determined by [1] available space for your sign, [2] how far away it needs to be readable, and [3] aesthetics, or the balance of "positive space and negative space", or lettering area and "white space" non-lettering areas. So let's address these all briefly.  FOR LARGE LETTERS 10" to 46" TALL GO HERE.

[1] Available space. If your sign is a fixed size, for example a 4x8 sheet of plywood, you can determine the available space for lettering by multiplication. As an example, if you will be using 10" tall letters, you will be able to get about 9-10 letters per line of wording on average.

FOR LARGE LETTERS 10" to 46" TALL GO HERE.

How did I determine that? 

As a rule of thumb, average letters are a little narrower than they are tall, so when you go to count the letters, you will also be leaving a little sideways space between the letters. For a rule of thumb, you can say that a letter takes up as much width as its height. That's to say that the height is about the same as the width plus the space inbetween the letters.
This applies to a standard block font like Helvetica or Arial; your choice of typestyle will affect this very basic calculation.

[2] How far away does your sign have to be readable? 

If your sign is for pedestrians, you can estimate 1-3 inch letters will be readable roughly 25-90 feet respectively. That's fine for someone passing your sign at 3-4 miles per hour, but how about car traffic? 

If the sign is facing the one lane of oncoming traffic, and cars are moving at about 25mph, that means you have about 5-7 seconds of readable time, no matter how large the sign. At 25mph, your potential customers are traveling 27-28 feet per second, so to be visible for up to five seconds, you need a minimum of 5.5" tall or larger lettering. It's different if the sign is perpendicular to the traffic, as now the lettering must not only be visible straight on, but it must be readable at a 90° angle, so a 10" letter may work much better in a scenario where the sign does not directly face traffic. 

FOR LARGE LETTERS 10" to 46" TALL GO HERE.

[3] Aesthetics, or how nice something appears, or how easy it is to read because of the portion of letters compared to the portion that is the "white space" around the letters, makes it easier to read a sign. If you can imagine a sign completely filled with letters, your eyes wouldn't be able to read that sign very well or at all. Basically, the eye recognizes words by the letter forms and uses the space around the letterforms. But that's for a very different article on typographic layout and form.

What do I need to have to make this turn out the best possible way?
The basic requirements for a very basic sign are [a] foam letters, [b] a yardstick or tape measure (preferably something as wide as the sign to help in laying out the letters), [c] cement for indoors or paint and silicone for outdoors and [d] to properly plan for and to allow yourself plenty of time. Arrange for help if you need it now, after you plan for the project. This should be a rewarding if not fun project, so leave the stress and time limits alone.

Using the yard stick or other measuring device, you can draw a faint blue pencil line as a "base line", so you know where to pace the bottom of your flat-bottomed letters like L or M or T. Rounded-bottom letters, like O or G, go slightly below the blue base line.

Before you glue or cement anything in place, assemble the wording on the background sign panel or board. If it's a wall, tape the letters in place temporarily with blue masking tape for painters. Now stand back and make sure the letters are well-spaced, evenly aligned and straight, and exactly where you want them to go.

You're almost there!
Now you can paint the letters or finish them however you like, and begin to attach them to the sign panel or wall.

Did I miss a step? Have a question I didn't cover?

Send me a comment or a note with a suggestion, and I'll send you a little thank-you gift.