Getting your CV looking and sounding right is a difficult task and many people have failed at this first hurdle. Not everyone is a natural writer and for some people, writing about themselves does not happen easily. You may wish to have a professional CV writer produce your CV for you or have another person edit it once it is completed. At the very least you should have someone else read it on your behalf.
You should take advantage of online templates to create your CV. This will mean that it is neat and tidy, has the right formatting and follows an accepted style. Unless you are very creative, it is best to stick to the tried and tested methods.
You need to understand that recruiters and hiring managers are under enormous time pressures and will be working to tight deadlines. They will need to make gut decisions based on first impressions and will be looking for a CV which captures their attention immediately. Remember that there could be hundreds of candidates for the role you are applying for.
How long? Your CV should be just two pages long unless it is for a very specific and technical role. It should be interesting enough for it to be read in its entirety. No employer will spend more than a few minutes reading any CV.