From Ground: Start by identifying the extent of common dandelion's root system. Once done, use your shovel or spade to dig around the root ball. Be careful not to damage the roots. If the roots have spread widely, dig deeper and wider. After loosening the ground around the plant, gently lift it out of the ground, preserving the root ball.
From Pot: First, water the common dandelion plant to dampen the soil. This makes it easier to remove the plant. Then, turn the pot sideways and while gently holding the common dandelion, tap the pot's edge on a hard surface. Then, the common dandelion should slide out with the soil intact. If it does not, you may need to use a garden trowel to ease it out.
From Seedling Tray: Moisten the soil and gently ease out the common dandelion using a small gardening tool or trowel. Be careful not to damage the young roots and remember, always hold common dandelion by its leaves, not the stem.