I also believe the first step should be researching what other card game frames that you like are doing well. Save lots of reference images, draw red circles and arrows saying "start doing this."

For me I really liked LotR lcg because the frames are very fitting for the setting and keep me immersed. I also what to point out sometimes card frames change their layout based on what type of card they're representing. So you see here we have bodies, items and happenenings all looking distinct at a glance. That kind of graphic design is tops.