Please add more :)
Will I be well received?
You are going above and beyond by lending a hand. You have experience, knowledge, stories that are unique to you. Share them with a genuine willingness to help and that is more than enough.
Take your time
Don't feel like you have to solve everything or that all the pressure is on you. Think of it as a partnership, in which you try to help in any way you can. Ideally, the mentee should also understand that you're there to provide guidance and share experiences, which is invaluable. Not to solve it yourself. Take your time and enjoy the process.
It does not have to be forever
As schedules and priorities change, work with your mentee when you both need to mutually part ways. Perhaps you both already accomplished a goal. Or things are busier now. That's okay! Similarly, parting ways does not mean you are strangers. Stay in touch!