It is advisable to minimize the use of filler words such as 'umm' and 'hmm' during the IELTS Speaking section, as they can detract from the clarity and coherence of your speech. Instead, focus on speaking confidently and fluently, without unnecessary pauses or hesitations. By practising mindfulness techniques and consciously avoiding filler words, you can enhance the fluidity and impact of your spoken responses, thereby maximizing your performance in this section.