Essentially, losing weight will come down to being in a calorie deficit. This means that you are consuming fewer calories than your body needs on a daily basis. Generally, subtle and gradual changes to your normal lifestyle will make it easier to stick with things long term and be successful with your weight loss goals. Some common areas that can be adjusted to help promote weight loss are in relation to your food choices, portion sizes, or activity level. Remember that patience and consistency is key with weight loss.
Having hypothyroidism may impact the amount of calories that your body needs throughout the day. This is why it can make weight loss more difficult. However, similar guidelines still apply for losing, gaining, or maintaining weight. There is no special diet, workout, etc. that has been shown to be better in managing the condition. However, it's important that your condition is managed medically as well. Be sure to stay in regular contact with your doctor for management of your thyroid.