First - trim fronds and root butt so that the bulb looks like this.
Next slice the bulb in half along it's narrow axis. At this stage the fennel could be brushed with olive oil, salted and roasted in a 350 degree oven.
Slice the halves into thin sections.
Thin Slices can be added to salads, stir fries, and soups
Small dice sauteed with onions makes a great base for many dishes.