The pedestal sink is broken down into two parts - the base or stand, and the sink. The sink mounts to a bracket on the wall and is set on top of the stand.
1. Make sure the wall is strong enough to bolt the sink into. If it's only drywall or plaster you should consider installing a blocking device under the surface of the wall to support the sink.
2. Freely set the basin in the position you want, propping it up with 2x4's so it's steady. Mark the position on the wall for mounting holes for the sink and the stand.
3. Drill holes corresponding to the marks drawn on the wall. Attach fasteners, then the drain and faucet lines to the sink. Next, attach the water supply lines to the faucet.
4. Now put the sink and stand back into position on the wall, but only bolt the sink into place. Support the sink using 2x4's and remove the stand from the sink.
5. Finish by attaching the drain and water supply lines. Then test for leaks
6. Move the stand into its final position and bolt it to the floor. If the pedestal sink doesn't require floor bolts, use adhesive caulk.
7. To finish, caulk the joint between the sink and wall, and smooth and blend.
Some of these steps can be rather complicated and Easy2DIY doesn't offer specific instructions. Once again, Vintage Tub & Bath recommends having a professional plumber install all fixtures.