Use stencils to give your message visibility, no matter what the nature of your message. Alphabet stencils command attention when giving instructions concerning an outdoor hazard and are an expedient way for children and adults alike to write their messages outdoors and indoors on a number of surfaces. Large alphabet stencils can be made to any size at home with a minimum of equipment and preparation, starting with paper, pencil and utility knife.
Open your word processor and choose a font that is suitable for stencilling. Fonts that are suitable may be called "stencil" or can be other fonts as long as they don't have floating islands within the letters. A floating island is an area that will be completely surrounded by cut-out space on your finished stencil, like the middle of a standard "o." These islands will fall out when you are done cutting your finished stencils, and need to be secured to the rest of the stencil with a small bridge of stencil backing. Stencil fonts will not have this problem.
Type a letter onto your word processor and adjust the size according to how large you would like your finished stencil. Use the "print preview" function to get an idea of how large your finished letter will be.
Print out your first letter.
Cut out the letter using your X-acto knife and the glass surface to cut on. If you are making stencils for one time use, paper will be sturdy enough. If you want a more permanent, tougher stencil, skip to the next section.
Repeat steps 2 through 4 with the rest of the letters and numbers you intend to use.
Lay your printed letter from step 3 in the first section on your poster board. Use a pen or pencil to trace over the edges of your letter, leaving an impression on the poster board beneath. Press hard to make a reliable impression.
Cut out the stencil along the impression left from step 1 using your X-acto knife.
Cut around your finished letter and put aside. Repeat steps 1 through 3 for the rest of the letters and numbers.
Choosing a font made for stencils will save you trouble later, but any font can be customised for stencilling by making small bridges to the stencil backing from any "islands" while cutting the stencils out.
X-acto and utility knives should be very sharp. Use a sharp knife so you do not have to apply unnecessary levels of pressure and risk injury.