There are loads of resources on how to plant citrus trees on the internet.
But here on the Gulf coast of Texas, we have to pay special attention to the dense soil that mostly consists of the old ocean floor. I live north-west of Houston, and there is no drainage at all in the soil in my garden.
The soil is either dense and wet or dense and dry.
This is a sectional view of the planting hole. Do not dig the hole deeper than the height of the root ball of the tree. Put the root ball at a slight elevation down in the planting hole for drainage and to keep parts of the root slightly raised above the area around. Fill back soil and soil conditioners as explained above.
Water and fill the rest of the soil around the trunk careful but firmly. Make a ring of mulch so you can easily stop the water from flowing away when you water manually the first period (year?). Keep mulch away from the trunk and the top of the root ball to prevent root rot.
Apply fertiliser when you see the tree starts to grow.