There is now a large collection of gimp and jpeg files of posters you can download for using at your asapuwa
Check out the Beautiful English Fonts page for fonts that work well in posters.
You can find links to English Sutta Translations here: English Sutta Translations
Here is a usage guide for making written materials, posters, etc. It covers important thinks like capitalization and punctuation.
Pali Diacritic typing tool
If you want to put the lines and dots on Pali words, download and run this piece of software. An icon will appear in your tray. Right click on it and you will see an option for “Keystrokes for Sinhala and Pali Transliteration”. Click on that and instructions will pop up to tell you how to type ā, ī, ū, ṭ , ḍ, æ, as well as an n-dash (–) an m-dash (—), etc.
Source code (only if you use AutoHotkey and want to change the software)
If you are familiar with this website, http://ucsc.cmb.ac.lk/ltrl/services/feconverter/ Then you will appreciate this updated version https://drive.google.com/open?id=0B-4tDjkCm46Uai1QeG1NVUdkOUU that helps tranliterate unicode Sinhala into standard English letter transliteration.
Now a days, many fonts have the letters you need for Pali. The letters with dots, especially ṇ, ṅ, ṁ are sometimes missing. Microsoft Word will often use letters from another font if they are missing. Check carefully. Many special fonts for Pali can be found at Bhikkhu Pesala’s Font Page.