Lift Car with a floor jack. use a jack stand to hold it up. chock all wheels that are left on the ground, because this can be a pretty dangerous way to do your own tie rod. I've done two this way so far, though, with no problems.
Get on the lock nut of the tie rod end, and turn it clockwise 1 turn. It will be difficult to start, but once free, will turn easily. This will back it off from the tie rod end.
Remove the tie rod end from the wheel knuckle. I can't remember if there's a cotter pin holding the nut on or not on the Focus. If there is, remove it before undoing the nut. It's self explanatory.
unscrew the tie rod end from the tie rod. Count the number of turns it took to remove it, and write that number down for later.
Remove the lock nut that you backed off.
Cut the Tie rod dust boot clamps with shears, or pull them off with a screwdriver, pliers, or whatever. You will need to replace them. I used screw-tighten hose clamps to replace them, because my boot clamp tool would not fit in there.
Remove the dust boot. There is a hose connecting both sides of the steering, it runs between the two dust boots. Nothing but air in there, just make sure you keep track of it and hook it back up when you're done.
Turn the steering wheel as far away from the side you're working on as possible. If you're working on the driver's side tie rod, turn the steering all the way to the right. Vise versa for the passenger side.
That guy up there was right. there are no flats for getting on the ball joint with a wrench. snap onto it with a pipe wrench instead. It will work. You may need to firmly kick or apply foot pressure to the pipe wrench to back it off.
When it comes out, replace it. I used blue-color (medium) thread lock on the part that goes into the steering rack. Tighten it well, with the pipe wrench or an open-end wrench on the flats.
Replace the tie rod dust boot. Place the hose clamps on the boot beforehand. Make sure the air hose that connects the two boots together is connected properly on both ends.
Tighten the hose clamps. Yes, I know, it's a pain in the ass.
Put the tie rod lock nut on the tie rod, move it pretty far down the tie rod threads.
Replace the tie rod end. Only screw it on the same number of turns you used to remove it.
back the lock nut against the tie rod end, firmly. NOTE: DO NOT USE THREAD LOCK COMPOUND ON THE OUTER TIE ROD END, THE TIE ROD LOCK NUT, OR THE TIE ROD END ATTACHMENT NUT!
Put the wheel back on, and go get an alignment.