Firstly: What must be Avoided during Ihram
One in ihram must avoid the following:
1. Indecent speech or acts. This is not allowed whether or not one is in ihram, but the restriction is more severe with respect to ihram because of the sanctity of the act of worship.
2. Irreligiousness, which is all acts of disobedience, including the restrictions of ihram.
3. Arguing during Hajj, meaning disputes over falsehood – particularly with companions and servants – or arguing about things that have no value. That is because doing so stirs up evil, causes enmity, and keeps one busy from remembrance of Allah. As for arguing in the best manner to present the truth or reject falsehood, there is no harm in it.
Secondly: What is Permissible during Ihram
1. Trade and production
A pilgrim may trade and produce goods during Hajj.  However, scholars deem it mustahabb that he not engage in trade such that his heart be preoccupied with the task at hand, divested of the muddiness of this world and the attachment of the heart to it, even though doing so does not divest a legally accountable person of the sincerity due of him. This is the chosen position of Ibn Qudamah, al-Nawawi, and al-Shinqiti.
It is permissible for one in ihram to have cupping (hijamah) performed if he has a valid reason to do so. Nothing is due of him if he does not shave any hair. Consensus on this was related by Ibn `Abd al-Barr, al-Baghawi, al-Qurtubi, and al-Nawawi.
3. Medical treatment with anything other than perfume
One in ihram may touch anything that is not perfume and use it as medicine. Consensus on this was related by Ibn `Abd al-Barr.
One in ihram may perform siwak (brushing one’s teeth). Consensus on this was related by Ibn al-Mundhir and al-Hattab.
5. Slaughtering sheep, goats, cattle, and camels
One in ihram may slaughter sheep, goats, cattle, camels, chicken, and the like. Consensus on this was related by Ibn Hazm and Ibn Qudamah.