There are a few ways to make a mesh grid in Illustrator. The easiest way is to use the Pathfinder tool, which is located at the bottom of the screen. You can drag and drop pieces of mesh onto the grid, or use the arrow keys to move them around. The Pathfinder tool also lets you resize and move pieces of mesh with ease. If you want to create a more complex meshgrid, you can use the Mesh Editor tool, which is located at the top of the screen. This tool lets you create meshes with different shapes and sizes, as well as edit their properties such as opacity and transparency.