Speaking is marked on four things in equal measure: fluency and coherence, lexical resource, grammatical range and accuracy, and pronunciation. Strong students often sacrifice the first for the third — they stop mid-sentence, rebuild the grammar, and restart. Over a fourteen-minute test that trade is a bad one.
Fluency does not mean fast, and it does not mean flawless. It means your speech moves and your listener can follow it. Which means the skill to practise is recovery.
Rephrase instead of repairing. If a sentence is going wrong, do not reverse into it. Finish the idea a different way: "…what I mean is, it made the whole trip cheaper."
Use natural fillers, sparingly. "That's a good question", "let me think", "I suppose it depends" buy you a second and sound like a speaker thinking. What does not sound like that is "er… er…" repeated. One or two per answer.
Do not hunt for the perfect word. Say the nearly-right word and keep going. The examiner is marking the range you actually produce, not the one you were reaching for, and a four-second silence costs more than an approximate noun.
Let small errors go. If you say "he go" and notice, correcting once is fine and shows control. Correcting every article and tense turns your answer into a rehearsal and wrecks the rhythm.
Record yourself often, because fluency is the one criterion you genuinely cannot judge while you are speaking. Play it back and count the silences over two seconds. That number is your score for this skill, and it comes down with practice faster than anything else in the test.