1) Education and grades. If you have written it down then it can be checked, so don’t guess or make it up. You may feel your effort deserved a 2:1 degree, unfortunately your exam board has to agree. Companies check this – a lot!
2) Job Title. I would really like to be called “Emperor” but that is not my actual job. Your job title is the role written into your employment contract and will be what is given on a reference. If it is different, companies question what else on your work history could be inaccurate.
3) Actual dates of employment. Working from December 2016 to February 2017 is 3 months, as opposed to saying 2016-2017 which intimates a much longer tenure. Nobody wants to show employment gaps but this is one of the easiest checks to make. You are deliberately bending the truth so what impression do you think this gives a potential employer?
4) Details of your experience. There are two things here. Very few people are masters of many skills so listing 20 technologies you are expert in is asking for trouble. Equally, just because you can order a few beers in Spanish, it doesn’t mean you have Spanish as a language. These may look good on paper and may well open a door for you, but down the line it is also likely to get the door slammed right back in your face.
5) Filling in gaps in your employment with “travelling” and “working in the family business” will often be met with a desire to have you prove it. Seriously, some companies will ask for flight tickets and references!