1 - To add a mesh fill to a selected object, press M to apply a mesh, and then drag colors to the mesh.
2 - Double click on any grid line to add a grid line.
3 - Shift + double click on any grid line add a node, which is useful for adjust the shape
4 - Select a color from the color palette and drag it to an area where the grid lines intersect to add a new color to the mesh
5 - Select a point where the grid lines intersect and then use the eyedropper off the Property Bar to copy a color to this point in the mesh.
6 - If you select a node and Ctrl+Click on any color of the Color palette, the color you are clicking on will add 10% of the color to the node on the mesh.
7 - If you want to have a lighter color, Ctrl+Click over the White color. If you want to have a darker color, Ctrl+Click on the "Rich Black" (the last color of the CMYK color palette).
8 - To add transparency, select one or more nodes and choose the Transparency level on the Property Bar.
9 - Start with a basic shape, as simple as possible, then add nodes and colors. A complex mesh can be hard to handle.
10 - Symmetrical nodes produces smooth shades of colors, cusp nodes produce sharp transitions between colors.  

Tips provided by Ariel Garaza Díaz, CorelDRAW Master.