A continuing trend in Pokemon GO (and the Sixth Generation of Pokemon moving forward) is the ability for trainer customization. With these options, you can personally make and adjust what your trainer looks like (at the beginning of the game with professor willow, as well later while playing). You can make your trainer look like yourself in real life or your wishful desires of what you'd look like as a trainer, or frankly how ever you'd like them to appear. This features gives the game another level of personalization, yet another realm of originality.
The first option a player has is whether they'd would like their trainer to be male or female. The second option a player has is the choice of the skin tone their trainer has, having the choice of four different shades and pigments. Next, a player can adjust the color of their trainer's hair. This setting has the most options, sitting at a grand total six possible choices to decide from. Along with their selection in hair color, a player can also choose from five different eye colors.
From there, the trainers are allowed to pick out certain accessories and articles of clothing. The player has many possible options to select from for each category (Hat, Upper Wear, Lower Wear, Gloves, Socks, Necklaces (Females), Belts (Females), Shoes, Backpacks), usually differing in both style and color from the next. With the 2nd Generation Update, many new clothing options were added, as well as a few that cost PokeCoins to obtain. (Some articles of clothing even require a certain level before purchase.) During certain Promotional Events, players will also receive free exclusive clothing.
Lastly, after catching their starter Pokemon, a player with have to give Professor Willow a name (nickname) they would like to go by. This is the name people from around the world will view your character and profile as, and it can only be changed once after first deciding upon one. This, as well as all the other customizations to your trainer, can be altered at anytime through the Player's Profile.