You just planted a fruit tree. Hooray! But now you wonder how you should prune it. The answer is ... don't!
Give the poor thing a good growing season before you break out the pruning shears. It needs a solid root system, and to grow roots it needs energy. Where does it get energy? The sun! via the leaves! So don't start lopping off leaves!
Most trees also want to be pruned during dormancy. Even trees that do not experience dormancy should get a growing season to establish before pruning.
The only time you want to prune immediately after planting a tree is if a branch is growing in a grossly odd and unhealthy way, like crossing over another branch such that they will rub in the wind. I get that you're excited, and want to set the tree up for success, but trees reward patience.
Pics of my nectarines. Planted last year in May, pruned lightly in January.