Decide what your ideal size of each piece will be, cut some paper patterns that size and tape to the wall in different configurations until you find the best arrangement. Or post photos of the options here; I'm sure people will have helpful input.

My suggestion would be to center the grid on the wall and have equal spaces on the left and right, ( ideally your artwork should take 2/3 of the wall) leave about 1" of space between frames the total width will depend on your artwork/frames, install the first row no less that 30" from the floor and leave at minimum 15" from the ceiling to the top of the last row

if you were to have only one piece of artwork the center of it is usually at eye level, more or less 60" above the floor

like this

Keep the footprint of the gallery within 75% of the table's length for balance.