Not Sticking to the Bed

Solution 1: Build platform is not level

Build platform is not level

Solution 2: Disabling cooling fan for the first few layers

Disabling cooling fan for the first few layers of your printer so that the initial layers do not cool down too quickly.

Solution 3: The build platform surface

The build platform surface (tape, glues, and materials)

Solution 4: Brims and Rafts

When all else fails: Brims and Rafts