At first I wasn't doing the plant-based diet right, I was just eating meatless. Then I began replacing meat with the prepared meat analogues you'd find at the grocery store as I was trying to round out my nutrition.
Once I knew this was going to be a more long-term thing I began exploring vegetarian cuisine a lot more. Once I was out of college and working from home and was able to cook from home so it wasn't until I was a vegetarian for about five years before I started being more intentional and well-rounded in my diet.
I'd recommend anybody trying out diets to get plugged into a community where there are fresh and relevant recipe and lifestyle ideas being discussed. I was 'in isolation' just doing my thing for the first half decade, then I discovered /r/vegetarian and /r/vegan and my life has been a lot richer because of all the great ideas I can use to spice up my life. I wish I had (bothered?) gotten plugged into that sooner!