I would not do anything until it gets older and stronger. Also, if you want it to fruit you will need to graft it.

By Graft, you mean, to cut some bark away, then put another piece of a plant from another tree in it and let them "meld" together, right?

If that is what you mean, and if that is the only way it will ever fruit, I'm probably boned because I don't know where I'd get access to one of those pieces to graft onto it.

Do you have to graft in its early stages? or can you graft when its older?

I guess I wouldn't mind it fruiting one day, but if its a PITA to get this one to do that, I'm not too worried about it. Avocado's aren't that expensive :)

Why will it not fruit if not grafted Tim???? Grafting is like making plant being older so it will fruit sooner. There is no need to graft in my opinion !

There is a tree by my house that was never grafted. It is almost 30 years old and has never fruited. Don't take my word for it. Do some further research.

I have two mature seed-grown avocados in my southern California yard. Both began bearing fruit at five years age. They say that the fruit from a seed-grown tree will be inferior to the carefully selected commercial types, but my fruit seems to me every bit as good a commercially grown avocados.

It's my understanding that when grafted at age one year, trees may bear fruit the following year. Grafted trees will also bear fruit true to the scion type, e.g. if you want a true Hass avocado, you must graft a Hass bud to your tree.

If having fruit a few years sooner, or having a specific type of fruit is important to you, then you would need to graft. But frankly, grafting successfully isn't trivial. I've tried repeatedly without success. I'll keep trying because it's a skill I want to learn, but it would be far easier to just buy a Hass at the nursery.

As Tim points out, there are no guarantees with seed-grown trees. You might end up with a sterile one, or one that gives poor quality fruit. I understood that from the get-go. That's why I planted two trees. To improve my odds. I ended up with two good ones. :-)