How exactly is tayammum done and when is it permissible to do it?
The things which break normal wodhou break this one too or are there other things which break tayammum wodhou?
If one can’t use water on the face only, can they do normal wodhou and use tayammum for the face?
Re: Tayammum
Peace LP,
I broken up your comments to answer you in best. 
How exactly is tayammum done?
Stroke the earth lightly with hands and below off the dust, then pass hands over same places like we do ablution while using water. (citation required).
If one can’t use water on the face only, can they do normal wodhou and use tayammum for the face? and when is it permissible to do it?
Tayammum is permitted when it is not possible to use water due to it being unavailable, or when some harm is feared from using it, due to sickness in the body or severe cold.
The things which break normal wodhou break this one too?
Yes.
**or are there other things which break tayammum wodhou?
**Yes in addition, tayammum invalidated by the presence of water for the one who (earlier) did not find it, and the ability to use it for the one who had been previously unable to do so.
Bonus comment: Prayer which a person has already performed in above state are correct, and that person is not obliged to repeat it.
Re: Tayammum
Peace LP
The above posted is in general. However, there are some minor holes due to difference of opinions. If you need to understand in better way, then you may pick any book of Fiqh and read about Tayammum.
Re: Tayammum
So tayammum only for the face and the rest normal wodhou?
Re: Tayammum
O you who have believed, do not approach prayer while you are intoxicated until you know what you are saying or in a state of janabah, except those passing through [a place of prayer], until you have washed [your whole body]. And if you are ill or on a journey or one of you comes from the place of relieving himself or you have contacted women and find no water, **then seek clean earth and wipe over your faces and your hands [with it]. **Indeed, Allah is ever Pardoning and Forgiving. (43)surah An Nisa
JazakumAllah khair sister, your questioning are reminders for me.
Re: Tayammum
Peace LP,
Tayammum consist on two strikes on the earth (1) for face and (2) washing hands, elbows and feet. See the below Shafii Method:
The essentials to a proper performance of ablution with sand are :—
1- An actual removal of the sand to the limbs ; 1**
No feet are required. Face first, then right hand and then left. That is it.
Also, some rulings say that only one obligatory salah can be performed per tayammum, but that does not sound right to me
Re: Tayammum
Peace TLK,
Actually one obligatory Salaah can be performed per Tayammum is according to Shafii method, however, according to Hanifi method, one may read Salaah as many as he wants, as far I know. I agree with you that feet is not included. However, feet and moving hand on head is mentioned but it will become silent while doing Tayammum (Hanafi Book).