A method of forming an entry guide at an end of a tubular string in a wellbore can include conveying a forming device into the wellbore, and deforming the end of the tubular string from a cylindrical shape to an outwardly widening shape with the forming device. A method of forming an entry guide at an end of an expanded liner hanger in a wellbore can include outwardly expanding the liner hanger, thereby sealingly securing a tubular string in the wellbore, and deforming the end of the liner hanger from a cylindrical shape to an outwardly widening shape with a forming device.