Once you have spotted the urtuu, slow your pace- the herders all have aggressive dogs who will not be very welcoming if you thunder up to the ger. In addition, other riders may have come in before you and there is generally a throng, so cannoning into the vets and your fellow competitors might be seen as unchivalrous.
The urtuu manager or vet will sign you in to the urtuu and record your time.
You should unsaddle your horse and present it to one of the vets as soon as one is free. We have not rule-governed this activity, but be sensible - on day 1 where 25 riders may be in the ger at the same time, the vets are working under pressure to check and re-check everyone, so keep your pants on and wait your turn. Emergency help will ALWAYS take priority over routine race duties, so if a horse has been injured, the vets may be tied up.