Before you start you need to inspect carefully the rock and chart your route, depending on the availability of support points. You need have constantly three points of support, transferring to the next only one limb. You need to climb smoothly without jerking to keep your balance, energy and strength of the fulcrum.
You must have some skills or you will break a leg or injure a back, and you can even die. You can fall into the crevasse (расселина в леднике). You can freeze and your arms and legs may be numb, because of cold weather and wind.