This article about the figure of 8 knot is part of the e-book - Rock Climbing Basics: The Beginner's Guide.
Unless you are bouldering, you'll need to tie the end of the rope to your harness before you climb. The best way to do this is using a rethreaded figure of 8 knot. It's really important that you do it correctly, as this knot is what connects you to the whole climbing system and keeps you safe.
Try not to talk to someone or distract them while they tie in. Likewise, once you start tying your figure-8, keep going until you’ve finished before responding to any questions. Accidents have happened because climbers were distracted halfway through tying in and then fell with a half-completed or incorrect knot.
How To Tie In with the Figure of 8 Knot
Make a loop about a meter from the end of the rope. Wrap the end of the rope around the base of the loop, then push the end through the loop.
You should end up with an '8'. Make sure the knot is around 90cm from the end of the rope. The exact length varies with ropes of different diameters, but you'll soon get used to it.
Pass the end of the rope through both of the two points on the front centre of your harness – the same ones your belay loop runs through. It is important that the rope goes through your harness in exactly the same way as your belay loop does.
Use the end of the rope to 're-trace' the figure of 8 knot. Follow the twists of the rope starting from where the rope joins your harness.
Continue following the twists until you end up back at the start of the knot.
Pull the whole thing tight.
Make sure the end of the rope is around 25cm long. If it is shorter, you'll have to untie and start again. After this, you will need to tie a 'stopper knot'. Loop the short section of rope around the main length.
Do this twice, with the second loop closer to you than the first.
Push the end of the rope through these two loops, away from you.
Pull this tight too (make sure it's pushed right up against your figure of 8 knot).
Remember that your knot is not complete until it is tight. Be aware that stiff new ropes tend to loosen. Pull the knot super tight before you climb.
The stopper knot has no bearing on safety as long as you tied your figure-8 correctly, so don’t panic if it starts to unravel as you climb. The purpose of the stopper knot is to ensure that you have left enough tail to stop the figure-8 failing – a short tail could slip through the knot.
Also, if you left a long tail dangling without a stopper knot, it could be mistaken for the main rope when clipping quickdraws, or the anchor. Always tie a stopper knot for these reasons.
If you didn't have enough rope left to tie a stopper knot, you'll need to retie the figure of 8 so that you do.
It takes a bit of practise to judge just the right amount of rope from the start, but you'll get used to it soon.
Safety Check: Have You Tied In Correctly?
Visually inspect your knot, and your partner’s knot, before every climb.
If someone asks you a question or distracts you when you are tying your knot, wait until you have finished before answering. Do nothing else until the knot is complete.