For the consecration, the bishop comes to kneel in the middle of the church.
http://www.newliturgicalmovement.org/
The website of the Fraternity of St. Peter's apostolate in western Switzerland, centered around the general house in Fribourg, has a nice album of photographs of Confirmations recently held in the Church of St. Michael, part of the former Jesuit college of Fribourg. The sanctuary of this beautiful church is typical of early Jesuit works, very wide, with no liturgical choir, making it ideal for Pontifical ceremonies; under the main altar rest the relics of St. Peter Canisius, founder of the college, who died in 1597. The Mass was celebrated by Fr. Arnaud Evrat, F.S.S.P., in the presence of His Excellency Pierre Farine, the Auxiliary Bishop of Lausanne, Geneva and Fribourg, who performed the Confirmations. These photographs give a good idea of the particular ceremonies of the Missa coram episcopo, in which some of the rituals of the Mass (e.g. the blessing of the incense) are performed by the bishop at the throne, rather than by the actual celebrant of the Mass.