Intermittent exotropia is divergent squint, which only occurs intermittently. Myopic people have a tendency for this. If and when you are fit and healthy, you can control your eye muscles but when you are weak or run down with poor general health, tired or not concentrating, they decompensate and you show divergent squint.
Make sure you don’t need glasses, read or do close work from a distance of about 33 cm or more. Keep a healthy life style with balanced nutrition and exercises. Even eye exercises help in this situation. If it is cosmetically embarrassing or getting worse, you can have surgery to correct this.