There is a particular kind of modesty that creeps into resumes, and I see it constantly. Someone will have led a project that saved their department a genuine headache, or quietly become the person everyone turns to when something breaks, and then they will describe it on paper as "responsible for various tasks." It is not false. It is just nowhere near the truth of what they actually did.
This piece is not about formatting, fonts, or how many bullet points you ought to have under each job title. Plenty has been written about that already, and most of it says roughly the same thing. What interests me more is the part people tend to get wrong even once the layout is sorted: what you actually say about yourself, and how well it reflects the person doing the work.
You are not writing a job description
One of the most common habits I come across, and something I have been guilty of in the past as well, is people effectively rewriting their job description rather than describing what they did within it. There is a difference between "managed a team of five" and "took over a struggling team of five and brought turnover down to nearly nil within a year." The first tells me what your title implied. The second tells me something about you.
Employers already have a rough idea what a job involves. They do not need you to confirm it. What they are trying to work out, often quite quickly, is whether you were good at it and what that goodness actually looked like in practice.
Results matter, but so does the shape of the problem
Numbers are useful, and I would never talk anyone out of including them where they are genuinely true and relevant. But a number without context is oddly flat. "Increased sales by 20 per cent" tells me very little on its own. Was that against a shrinking market? A team half the size of your competitors'? A product nobody believed in six months earlier?
Give the number somewhere to live. A sentence or two of context transforms a statistic into a story, and stories are what people actually remember once they have put your resume down.
Ownership is worth more than you think
There is a nervousness some people have about sounding too confident, as though claiming credit is somehow impolite. I understand where it comes from, but a resume is not the place for that particular kind of humility. If you did the thing, say you did the thing.
This does not mean inflating your role in something a whole team achieved together. It means being precise about your part in it, rather than hiding behind passive language that could describe almost anyone. "The project was completed successfully" is a sentence with no author in it. Who completed it, and what did you specifically bring to that outcome?
Choose the version of the story that says something about you
Most jobs involve a hundred small tasks that nobody particularly needs to hear about. The trick is not fitting everything in, but choosing the handful of moments that actually reveal something worth knowing. Perhaps it is the time you noticed a recurring complaint nobody else had flagged, or the process you built because the old one kept quietly failing.
These are the details that separate one candidate from another who technically did the same job somewhere else. Anyone can list duties. Far fewer people can point to a specific moment where their judgement, initiative, or particular way of thinking actually changed something.
Let your personality show, within reason
A resume does not need to be dry to be professional. The language you choose, the examples you pick, even the small asides you allow yourself, all say something about how you think and communicate. I am not suggesting jokes or excessive flourish, but there is a middle ground between corporate blandness and unprofessional casualness, and most people sit far closer to the bland end than they need to.
Read your own resume back and ask honestly whether it sounds like you, or whether it sounds like a template with your name inserted at the top.
Be specific about what you are looking for next
This is often left out entirely, or reduced to a vague line about seeking "new challenges." If you know roughly what kind of role or environment genuinely suits you, say so, at least in your covering material if not the resume itself. It saves everyone time, and it signals that you have thought seriously about your own direction rather than simply applying broadly and hoping something sticks.
A final thought
The best resumes I come across read less like a form that has been filled in and more like a short, honest account of someone who has actually done things and thought carefully about why they mattered. That does not require exaggeration. It requires paying proper attention to your own experience and having enough confidence to describe it accurately.
Most people undersell themselves not out of dishonesty, but out of habit. Breaking that habit is, in my experience, one of the simplest and most effective things anyone can do before their next application.