A resume can become difficult to follow when too much information competes for attention. Applications are often reviewed quickly at first, especially when a panel has many to work through, so it helps to write for a quick read rather than a careful one. A resume that makes its main information easy to find is easier to assess.
Make the basic facts easy to locate
Keep your current field, employers, titles and dates easy to locate at a glance, rather than folded into paragraphs. If the work history takes effort to piece together, the substance of your experience may not get a proper look. Keep your name and contact details plain at the top.
Put the relevant material early
Whatever appears early on the first page is effectively your opening statement, so it is worth being deliberate about what goes there.
A short career profile, a few lines summarising your experience and strengths, is one common way to use that space, sometimes followed by a small number of specific career highlights. Neither is compulsory. Either way, if something is important to your application, place it early rather than relying on material deep in the document being noticed on a quick first pass.
Things that can waste the space
An objective statement describes what you want from your next role. The top of a resume works harder when it shows what you offer; what you are looking for can go in your pitch or cover material if it is needed at all.
A list of general qualities such as "leadership, communication, attention to detail" gives the reader little to work with, because it is a self-assessment rather than evidence. Specific experience and examples carry more weight. Completed qualifications and certifications are different and worth listing, though they usually sit later in the document.
Education placed at the very top can crowd out stronger material once you have work experience. Recent graduates with little work history are a reasonable exception.
A quick self-test
Give your resume to someone for about ten seconds, take it back, and ask what they remember. This is an informal readability test, not a simulation of how any panel works, but it is revealing. If they can tell you roughly what you do, where you have worked and one thing you achieved, the document is scanning well. If not, the top of the first page is the place to start fixing.
Next, see a clear and practical resume format for section order, dates, length and older roles.