You need to do your research on Saudi and ask your employer to guide you. Things change here daily and there are HUNDREDS of professions out there..........the requirements vary for each.  The ones which require degrees, diploma won't work...........the ones which don't require degrees e.g. labor, you are asking for trouble during labor inspections and can't bring family with you.............the ones for which diploma can work e.g. welder, come with a skill testing exam.  It has become very difficult in Saudi now.
I can't guide you as on top of the complexity that I highlighted.........I may give you a profession which your employer may NOT have a visa for......because, it doesn't fit with their business activity. And on top, I see from your profile that you are British..........so getting something like a labor visa is a big red flag for ministry of human resources straight off as this profession is usually the domain of workers from the sub-continent e.g. Pakistan, India etc.
Posting the same question on multiple theads to posters who come in to ask their question and haven't been back in years, will not help you much. This is a discussion you need to be having directly with your employer and ask them what profession they will recommend for you..........keeping in mind your situation, nationality, the list of activities on their commercial registration, the visas by nationality that they have and tons of other factors. Based on your other posts, the profession you seem to fit are either marketing specialist (requires a degree and has been saudized to the extent of 30%) or strategy officer / manager / director (requires a degree). However, in most cases, marketing specialist visas are closed off on an on/off basis due to Saudization issues and many companies don't have strategy visas. On top of that, EVEN if you had a degree (instead of diploma in sciences), that would have still created problems because your degree is NOT relevant to the profession you are putting on your Iqama. In the past, you needed a degree and then could have worked in any profession.........now they match profession vs. degree in most cases (degree being absolutely necessary). That is why I am telling you to speak to your employer HR as it is up to them to find a way out.
Then you need to come back here and ask for a second opinion on what your employer recommended.  What I can tell you straight off, besides the fact that you will always be exposed during labor inspections (to fines and deportation because you won't be PHYSICALLY working a job that matches the profession on your Iqama) is that if you want to bring your family here, you WILL need to show immigration a degree (and this is a separate hurdle from the initial work visa). There are people who have ACCA/CIMA and similar high end qualifications but are not able to bring their families because they don't have a bachelor's degree and immigration doesn't recognize master equivalent qualifications as a degree..........tons of these experiences on these forums. And these people have work visas, Iqamas with the right profession as well as membership of the Saudi accounting body which has verified their qualifcation as matching the profession they are working in.
So read through my response carefully, browse the forum and read other experiences, speak to your employer and then think long and hard on your priorities before accepting anything in Saudi. As I said before, they are making it very very difficult for expats through these rules.
