The application of archaeomagnetic method as a dating tool in archaeology has intensified considerably in the last few years. The successful use of archaeomagnetic methodology depends on different factors and many efforts have been made for their clarification. Sampling is the first stage of each archaeomagnetic study. The careful selection and accurate orientation of the collected materials in the field are crucial for the obtained archaeomagnetic results. That is why detailed description of the fieldwork techniques used in Palaeomagnetic laboratory in Sofia is given and the advantages and disadvantages of the different baked clay types of materials are summarized.