You've been through it before. Being the new employee comes with anxiety, fear and excitement. The first day will influence your feelings as to whether or not you made the right decision in accepting the job offer. Helping a new hire feel welcome is important to building a strong relationship with everyone in the office.
Coming into a new work environment, a colleague will have many questions. Express sincere interest in helping her get situated and offer to answer any questions she has. Some individuals may be shy, so you may want to offer outright, "Are there any questions you have that I can answer? Just let me know." You can also help her understand that you've been in a similar situation of being a new hire; she will start to build rapport with you knowing that you understand what she may be going through.
Feeling like you belong is part of getting situated in a new work environment. The feeling comes with time, but it grows faster when the new hire is welcomed into social gatherings with colleagues. If you eat lunch with other employees, ask your new colleague if he would like to join you. This provides an opportunity for conversations about work and about life outside of work.
Make a point to check in with the new colleague at the end of the day and again at the end of the week if you are not already checking in on a daily basis as her direct mentor. You want to get a sense of how things are going in general. This interest in her shows your new colleague that you care and want to help her get situated in her new environment.
Compliment the Work
Receiving a compliment on work helps build a new colleague’s confidence. It lets him know he's doing something right and that he is making positive progress at work. Regardless of whether the new colleague holds a position below, equal to or above yours, the compliment will be appreciated.