We are finally on the middle of the sale season, and sometimes that can translate into buying things we don't need just because they are half price. In order to shop more thoughfully, here are five key pieces that you should invest on.

- Graphic t-shirts. We all know that the classic t-shirt and jeans combo is always a good escape to those "I have nothing to wear" days. However, that doesn't have to mean wearing a boring and plain outfit. The key to spicing up your look? Go for a funny and colourful top. Graphic t-shirts are everywhere right now, and you don't necessarily need to spend a fortune on a Gucci one. Just choose the right print for you and turn an average outfit into an Instagram-worthy one.

- Mules. And yet again, we have to mention Gucci on this one. Ever since their loafers went viral, a day hasn't gone by without a photo of someone wearing them on social media. That obviously means that every high-street store (and even more luxurious brands) has its own pair, which is always good news. Mules are basically an outdoor version of the slippers we wear at home, and that can only mean comfort. A type of shoe that can be worn in spring, summer, and even autumn depending on how you style them has to be a good choice of purchase, right?

- One-piece swimsuits. I've never been very keen on bikinis, so the fact that swimsuits are the most trendy thing right now makes me very happy. I find them very classy and flattering for every body shape, and don't even get me started on the pattern and colour possibilities. They may not be the best pick if your goal is to sunbathe, but they will definitely make you feel like a classy 60s Hollywood star.

- Wrap dresses. It was 1973 when Diane von Fustenberg debuted her first collection of wrap dresses, and ever since it became her signature piece. From the one that Cybill Shepherd wore on Taxi Driver to the (now viral) Réalisation one, this type of dress has lasted through decades, which can only mean that you would never go wrong with it. If you haven't already, it's time to shop for one and wrap it up.

- Raffia bags. Last but not least, we can't go through summer without the bag of the season. This year it's the time of those hand made-looking raffia bags, which have gone from being exclusively for the beach to daytime pieces for the city. Let's forget about the plain old school ones, right now there are tons of variations and designs to complete your summery look.