You may want to try a stretchier material which I find takes out less moisture- in some cases (and depending on your porosity) can be a benefit. I, myself, have plopped my hair using a king- sized jersey pillowcase, a long sleeved T-Shirt, a handkerchief, and even the PinkTag plopping towel which some of my clients have purchased in my shop.
My current favorite is called the Jac-o-Net nylon veil net, and is a wonderful choice for so MANY reasons! Firstly, the Jac-o-Net Veil Net is made of tulle, meaning that it completely aerates the curls. Why is this so great? Well, if you have long, thick curls that take a long time to dry you can either sit under your hood dryer with the net or you can TAKE OFF YOUR DIFFUSER and use your dryer directly! The veil keeps your hair tightly compressed and unable to frizz, yet still open to the air! Another reason I love this is that you can see through it to tell whether or not you have achieved the proper angle; you can see the curls compressed down like an accordion. The best part is that your gel will not stick! These nets are triangle in shape and there's plenty of room to wrap the tails around the front. Just throw these in your delicates bag when washing and they will not tear; or you can simply wash in the sink and hang/ blow dry.
There are many different takes on how you should plop, but I believe you should start with wet hair that already has your products of choice applied and then blot gently with microfiber or jersey before proceeding to plop. I also recommend a maximum of 20-30 minutes depending on thickness and length, but if you can go longer (or even overnight) that is great! Personally I follow what I call the 10-10-10 approach and I will explain that in a future post.