有了cas怎么办签证？
英国签证的三种类型为 1.Tier 4 Visa Student (一般中国学生申请都是这种)
2.Child visa for students under school age， called Child Student Tier 4 Visa; Children over the age of 7 should be sent to schools， so they don’t need a child student visa anymore but an adult one with parental support. Parents will have to get their own visas in that case if staying longer than six months in UK.
3.Visitor Visa， also applies to children above seven years old who are going to study as private pupils or international students at university level not covered by previous two types. It can also apply for short-term visits like holidays and business meetings etc. You might just get this type of visa when you enter Britain through tourist route on your visit there， which is usually the easiest way. If getting this kind of visa， you cannot work while studying or holidaying in London， however， it isn't applicable for visiting other parts of England， Scotland or Wales where you could do part time work. The rules vary from country to country since these three countries together compose United Kingdom though they all speak English language. Please pay close attention before applying any visa because once wrongly applied you may end up deported from UK！ This includes many Chinese tourists！
The first thing is deciding whether go to consulate abroad yourself or ask help from agencies here； both ways has pros and cons， I would say personally go to the consulate directly to make sure everything fits exactly into what you want especially details about documents required. However， it costs money if you choose third party company to do things for you although less expensive now due to internet development nowadays and more people doing them online rather than offline， e.g. using WeChat service such as “WeChat International” to book appointment for free then go pick up passport physically instead of sending it back to address provided after paying fee（this was how I went last year）. In fact， some people even send me pictures showing me how much cheaper agency services offer compared with consulates themselves－for example CNY500 for complete processing including collection/delivery of originals/copies/translation needed during application process