After you have the design created, you need to right click on the image and save it to your computer. (Be sure to remember where you save it to, I made this mistake when I first started out)
After the image is saved, the iron on process is pretty simple. First you will want to buy your shirts and transfer paper. Be sure to use dark transfers if you are putting the design on any color shirt besides white - or all white areas of the design will be the shirt color. If you are using white shirts, you can use either light or dark transfers. Light transfers are typically less expensive. Light transfers have a shiny finish to them and require that you flip/rotate the design before printing. I use dark transfers for all my shirts because I prefer the matte finish, more vibrant colors and to never have to worry about whether they need to be flipped or not. This is just personal preference. After a couple years of searching, I have found the best dark transfers on the market. You can find them on my webpage if you are interested. (link below)
After purchasing your tshirts and transfers - all you need to do is follow the instructions that come in your transfer package.
Be sure you wash your shirts first and do not use fabric softener or dryer sheets. You can print your designs in just about any software program. If you have just the basics on your computer, I think most people print from either Paint or Word. You will obviously need a color printer if you are printing colored designs and most transfer paper works with just about any inkjet printer. So, you don't really need anything special to make your own shirts. Oh wait, and you will obviously need an iron - ha ha.
If you have any other additional questions, please do not hesitate to ask. We were all new at this at one time or another and we are a friendly, helpful group of people.