If you find that you are using a specific group more frequently than others, you can sort your Field Groups so the group you need is always at the top. This can be done from within the Field Editor which is in the hammer icon.
Once there, you can click on the Groups button and select Sort Groups.
You will see columns for each of your different Field Groups. You may need to scroll to the right to see all of them.
Find the group you want to move and click on the six dots in the upper left corner next to the group name. Drag and drop the column in to the order you want.
Once you are done, click on Close in the lower right corner.