Drilling methods can be selected based on actual needs and conditions. Common drilling methods include:

The rotary drilling method: It is a common drilling technique that involves rotating the drill bit to cut through obstacles such as rock and soil within the borehole.

2. Drilling Rod Jetting Method: The drilling rod jetting method is a technique that utilizes high-pressure fluid within the drilling rod to move soil, rock, and other strata materials by rotating the drill bit.

3. Mechanical Breaking Method: The mechanical breaking method involves first creating a hole at the wellhead, then inserting tools such as a rotating blade and chisel into the hole, and using mechanical vibrations to crush soil and rock.

4. Floating Drilling Method: The floating drilling method is commonly used for drilling offshore oil and gas fields, as it reduces the damage to the seabed by lifting the drill bit.

5. Liquid Nitrogen Drilling Method: A new unconventional drilling technique that fractures formation rock through the volume expansion and high-speed jetting of liquid nitrogen.

In summary, selecting a drilling method requires considering geological conditions, drilling objectives, and equipment capabilities, among other factors. Different methods have their own pros and cons, and it's necessary to weigh the benefits and drawbacks in practice to choose an appropriate drilling method.