Here is an idea: Go to university to get a degree and whilst you are there join the reserves, THEN as you are coming up for your final year at uni apply for a commission.To get the best of both worlds
That will give you some soldiering experience, you could even go off and become a reserve para, get your wings, do a basic brecon course and some other bibs and bobs. If you are a student and you speak very nicely to the reserve units admin officer and permanent staff instructor they can keep you very busy through your long summer vacation period and probably easter too. You would be amazed at the courses available to be done.
Tip: If you join the reserves do not go shouting to the management about how you are only doing it till you graduate as you want to apply for a commission. Some may take offence to you not wanting to stay in the reserves and limit the things you can do. Give it a year before mentioning to the admin officer that you are seriously thinking about applying for a commission as a regular.