Working holiday visas are generally intended for people aged 18 to 30.The visas are are usually valid for a year or two and have all sorts of restrictions on what type of work can be performed.It is usual that you will be restricted to non-professional type of work and you may only be able to work for one employer for maximum of 3 months at one time.Rules change from country to country, so it would be best to check with the embassy involved