そうすると, a combination of 然（そ）う (an adverb meaning ‘like that’, or ‘as such’) する and the 接続助詞（せつぞくじょし） と, expresses that ‘once (A) was done, (B)’, or ‘upon (A), (B)’.
そうすると is usually used at the beginning of a new sentence, to highlight something that occurred due to the circumstances mentioned in the previous sentence/statement.
As a stand-alone statement,
そうすると is classified as a 接続詞（せつぞくし） (conjunction).
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もう少（すこ）し遅（おそ）く走（はし）ってみれば。そうすると、もっと長（なが）い距離（きょり）走（はし）れるよ。
Try to run a little slower. Once you do that, you will be able to run a longer distance.
食（た）べる前（まえ）に軽（かる）く炙（あぶ）ってください。そうすると、もっと美味（おい）しく食（た）べれます。
Please roast before eating. Having done that, it will taste even more delicious.
The ‘result’ that
そうすると conveys, should always be one of two specific things. Something that the speaker has no control over, or a conclusion/determination that the speaker wants to confirm is correct (based on their understanding of the previous statement).
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この餌（えさ）を使（つか）ってみ。そうすると、もっと大（おお）きい魚（さかな）が釣（つ）れるよ。
Try using this bait. If you do so, you'll be able to catch a bigger fish. (Whether a fish bites or not cannot be controlled)
1993年（ねん）生（う）まれなんですか？そうすると、29歳（さい）と言（い）う事（こと）ですね。
You were born in 1993? So that means that you are 29, right?
When
そうすると is used to draw a conclusion about another person’s statement, the translation is closer to ‘so you mean to say (A)’, or ‘if so, then (A)’.
Although 然（そ）う has a kanji form, this particular word will almost always be written in hiragana. This is true for many different expressions that use そう, not just そうすると.