Some designers create general T-shirts designs, others only go for special occasions and the Kennesaw State Owls Men’s Basketball 2023 NCAA March Madness The Road To Final Four Shirt also I will do this rest do both. If you are a beginner I would advise to rather pick a niche, get it going and only later start a second general store. This way you can concentrate all our energy and creative art on one niche which can save you time. money and effort in the long run. #pieterhb T-shirt designers main goal is to have a high resolution and quality designs that could be printed on T-shirts , so they use softwares that work with vectors most of the time to develop that high quality design , because vectors quality never get down no matter how much enlargement you did to it. So softwares that could be used are like adobe illustrator , coreldraw , and you can use adobe Photoshop to make some mock ups to see how would the T-shirt look like in real life when someone wears it