Girls, who planned pregnancy, please tell me how you prepared? Did you…

Girls, who planned pregnancy, please tell me how you prepared? Did you change your diet? Quit smoking, for example? Do you need to do any tests? I have only bad eating habits, but my husband sometimes smokes electronic cigarettes. How will this affect everything? I haven't started folic acid and iodine yet. But I drink omega and calcium. When do you plan to take these vitamins, should I stop taking them or drink with Iodine? With the first child, I didn't worry much, but now I'm worried (please share ??).