As this is an essay question, I think the most useful way of practicing is to show you the three main things people will fall down on and we can practice are the following. I'll go through them here, and show how you can avoid these pitfalls using this question as an example:
1) Spanish Language: First off we need to make sure that what you want to get across is accurate, beautiful Spanish. This is something we can work on together by practicing vocabulary, tenses, grammar, but is not specific to this question.
2) Content: What questions could they ask? How does the question tell us what they are after? Therefore which vocabulary can we learn that will help with this? And what examples could you give to explain why you are right? Let's learn some sentences which you can use in essays to start, make and end your points.
3) Essay-writing: How do you plan an essay to make sure you gain marks, within the time given? Remember the examiners say they are looking for: "a fully relevant" answer, that shows you know what you're talking about by "logically" (step-by-step) explaining what you mean. Do this in an "organised" way, with the help of some examples and you're sorted! You'll have around 35 minutes (leaving some reading time) to answer this question. The best way to make the most of your time is by planning!
I would plan my essay in 3 paragraphs: (I suggest planning in Spanish to list your 3 topics, so you remember good vocab you can use in your essay and how to explain your examples). This is not "the answer" - when you plan yours you should plan using the vocabulary that you know you can use!
ejercicio y pasatiempos: incluiré el fútbol, el baile; yo paso mucho tiempo con mis amigos los fines de semana; se debe fomentar los deportes y estar sociable, como en clubes en la escuela; para divertirse y vivir en un estilo de vida saludable
una dieta equilibrada: 5 porciones de fruta y verduras; un litro de agua al día y comida lenta; utilizarlo para pasar tiempo con familia y amigos en casa; la comida rápida puede contener mucha grasa y sal, y no es un problema grande en sí mismo, sino se debe limitarla
abuso: del alcohol y la droga; puede arriesgar su salud y seguridad, y son muy adictivas; y comida rápida; rechaze exceso en lugar de moderación y hábitos saludables; la presión social;
Remember you also need to write a short introduction and conclusion that sum up your answer to the question you've been asked. For example:
Hoy en día, para vivir una vida larga es esencial que se tome en cuenta tres cosas: el ejercicio, la dieta equilibrada y evitar el exceso (especialmente de la comida rápida y el alcohol).
Nowadays, to live a long life it's essential that you take three things into account: exercise, a balanced diet and avoiding bingeing (especially of fast food and alcohol).
Utimamente, he mostrado de los tres elementos para vivir la vida más larga son... / Ultimately, I have shown that the three elements in living the longest life are...