If you don't have a carpetted floor...well even if you do, as long as you have a table somewhere nearby, ground yourself with your case still plugged in, and keep yourself grounded as you set the stuff on the table. Handle everything carefully, avoiding capacitors and connector edges. When you grab your components to reassemble your computer, do the same thing, keep yourself grounded while bringing the components close to you, and again remember to handle everything carefully.
Or get some antistatic bags 🙂