A method of operating a magnetic resonance (= "MR") apparatus having a superconductive MR magnetic coil system which is disposed in a vacuum vessel and is dry in MR measurement operation (= "cryogen-free") and having a cryostat for cooling the MR magnetic coil system which comprises a neck tube that leads through an outer shell of the vacuum vessel to the MR magnetic coil system, wherein a cooling arm of a cold head is disposed at least partly within the neck tube, wherein a closed cavity which is formed around the cooling arm is sealed in a fluid-tight manner with respect to the MR magnetic coil system to be cooled and is at least partly filled with a cryogenic fluid in the normal operation of the MR apparatus, characterized by the following steps for autonomous cooling down of the MR magnetic coil system to a cryogenic temperature at which the superconductive MR magnetic coil system can be charged with current: measuring the current temperature T ist in the MR magnetic coil system and comparing T ist with a definable first temperature target value T1 soll from which the vacuum vessel is to be pumped out; if T ist > T1 soll, activating a vacuum pump disposed outside the vacuum vessel and opening a first barrier valve in a vacuum conduit that leads from the vacuum pump into the vacuum vessel; measuring the current pressure P ist in the vacuum vessel and comparing P ist with a definable first target pressure P1 soll at which the MR magnetic coil system is to be cooled down to cryogenic temperature; if P ist < P1 soll, activating the cold head for cooling of the cooling arm; measuring the current temperature T ist in the MR magnetic coil system and comparing T ist with the first temperature target value T1 soll; if T ist < T1 soll, closing the first barrier valve and switching off the vacuum pump; further measuring the current temperature T ist in the MR magnetic coil system and comparing T ist with a definable second temperature target value T2 soll at which the operating temperature of the MR magnetic coil system for MR measurements has been attained and when the condition T ist ≤ T2 soll has been attained, transmitting the information to the cold head that the second temperature target value T2 soll shall be maintained. measuring the current temperature T ist in the MR magnetic coil system and comparing T ist with a definable first temperature target value T1 soll from which the vacuum vessel is to be pumped out; if T ist > T1 soll, activating a vacuum pump disposed outside the vacuum vessel and opening a first barrier valve in a vacuum conduit that leads from the vacuum pump into the vacuum vessel; measuring the current pressure P ist in the vacuum vessel and comparing P ist with a definable first target pressure P1 soll at which the MR magnetic coil system is to be cooled down to cryogenic temperature; if P ist < P1 soll, activating the cold head for cooling of the cooling arm; measuring the current temperature T ist in the MR magnetic coil system and comparing T ist with the first temperature target value T1 soll; if T ist < T1 soll, closing the first barrier valve and switching off the vacuum pump; further measuring the current temperature T ist in the MR magnetic coil system and comparing T ist with a definable second temperature target value T2 soll at which the operating temperature of the MR magnetic coil system for MR measurements has been attained and when the condition T ist ≤ T2 soll has been attained, transmitting the information to the cold head that the second temperature target value T2 soll shall be maintained.