The 1st house describes your outward behavior. It involves your disposition, appearance, manners, and sense of self. The 1st house indicates your outlook on life and helps you to project your unique talents into the world. It is governed by Aries.
The positive use of the 1st house is that it helps you to put your best foot forward into the world. The negative interpretation is that you can get caught up in excessive ego issues or the need to show off due to self-esteem or self-worth challenges.
The1st house often indicates activities that you take into the world. An Aries 1st house may be athletic and prefer to wear bright, fiery clothing. A Pisces 1st house may appear dreamy and illusive, preferring gentle colors like the blue of the ocean.
When you have natal planets in your 1st house, the planet flavors the way you project energy into the world. If you had Mars in the 1st house, for example, you passionately and courageously pioneer new paths in the world. However, you may need to work through anger issues or the tendency to not complete projects.