First, you’ll need a convection-style oven (not a toaster oven) with enough space to hold the products you want to decorate. The oven you choose needs to be dedicated to producing sublimatable products and should never be used for cooking food.
In my opinion, you should avoid a small oven and purchase a medium to large oven to accommodate the larger products and higher quantities your shop will soon produce. The good news is even a full-size convection oven is a relatively low-cost investment.
Second, you’ll need an internal oven thermometer to monitor the oven’s actual temperature instead of relying on its dial settings. Lastly, you’ll need a heat gun to shrink the film sleeves onto the substrates. Heat guns can be found at almost any home improvement store – we bought ours at Harbor Freight for around $15.