An apparatus adapted for performing a plurality of operation steps of a dialysis process, said apparatus comprising: a process controller for controlling the apparatus to perform the operation steps of the dialysis process, monitor process progress of the dialysis process and monitor sensor inputs from sensors of the apparatus; and a user interface, UI, comprising a display, an input device and a UI controller, wherein the UI controller is connected to enable presentation of graphical data on the display, and wherein the UI controller is connected to enable user interaction with the graphical data and connected to exchange information with the process controller, wherein the exchanged information is based on the user interaction via the user interface and monitoring of process progress of the dialysis process and sensor inputs from sensors of the apparatus monitored by the process controller, and wherein the UI controller is configured to represent each of the operation steps by one or more operation step items, each of which is a graphical item suitable to be presented on said display, and wherein the amount of operation guidance information of the operation step items is selectable by the operator during the dialysis process to be in one state among a set of states comprising at least a first and a second state, wherein the second state provides a larger amount of guidance than the first state through the dialysis process, and the operator is enabled to toggle between the states during the dialysis process, wherein at least one of the operation step items comprises operation substep items that represent substeps of the at least one operation step by at least one of operation guidance, parameter setting and status information, and wherein the UI controller is arranged to enable displaying of the operation substep items upon displaying of the corresponding operation step item when in another state than the first state, and wherein the UI controller is arranged to enable the displaying of a subset of the operation substep items upon displaying of the corresponding operation step item associated with the subset of operation substep items based on an input from the operator when in the second state, wherein such enabling based on input from the operator overrides any corresponding disabling of the displaying of the operation substep items by the UI controller when in the first state. a process controller for controlling the apparatus to perform the operation steps of the dialysis process, monitor process progress of the dialysis process and monitor sensor inputs from sensors of the apparatus; and a user interface, UI, comprising a display, an input device and a UI controller, wherein the UI controller is connected to enable presentation of graphical data on the display, and wherein the UI controller is connected to enable user interaction with the graphical data and connected to exchange information with the process controller, wherein the exchanged information is based on the user interaction via the user interface and monitoring of process progress of the dialysis process and sensor inputs from sensors of the apparatus monitored by the process controller, and wherein the UI controller is configured to represent each of the operation steps by one or more operation step items, each of which is a graphical item suitable to be presented on said display, and wherein the amount of operation guidance information of the operation step items is selectable by the operator during the dialysis process to be in one state among a set of states comprising at least a first and a second state, wherein the second state provides a larger amount of guidance than the first state through the dialysis process, and the operator is enabled to toggle between the states during the dialysis process, wherein at least one of the operation step items comprises operation substep items that represent substeps of the at least one operation step by at least one of operation guidance, parameter setting and status information, and wherein the UI controller is arranged to enable displaying of the operation substep items upon displaying of the corresponding operation step item when in another state than the first state, and wherein the UI controller is arranged to enable the displaying of a subset of the operation substep items upon displaying of the corresponding operation step item associated with the subset of operation substep items based on an input from the operator when in the second state, wherein such enabling based on input from the operator overrides any corresponding disabling of the displaying of the operation substep items by the UI controller when in the first state.