Metal Detecting started in the UK in the 1970s and many archaeologists saw uncontrolled detecting as a threat to the archaeological record. This led to the 1979 Ancient Monuments Act, which banned detecting on Scheduled sites, unless one is detecting under the supervision of Historic England ( I have done this twice)

I was the National Council for Metal Detecting's expert in Environmental Stewardship  between 2009 and 2014 ,which are mainly concerned with preserving flora, fauna, stone walls etc. on farmland, but which put some restrictions on archaeology and metal detecting. 

This all might come over as rather negative, but in reality it is no more than putting a seat belt on when in a car ( and ensuring that it is taxed and insured).

I live in Surrey, about 20 miles from a village called Wanborough, between Guildford and Farnborough, where some illegal detecting in 1983-84 by trespassing "nighthawks" resulted in about £12m worth of Romano-Celtic coins and artefacts being stolen. Surrey Archaeological Society reacted by lobbying Parliament to draw up the 1997 Treasure Act, which has been amended many times since then. I could explain most of this to any u3a member but would not put the details on the website.

• the legal framework (The Treasure Act),
• The Code of Good Practise,
• membership of National Bodies (e.g. National Council for Metal Detecting) - which includes third party insurance,
• permissions to detect from landowners - and contracts for landowners to sign,
• equipment - and the expense of acquiring,
• level of fitness,
• researching land before detecting (e.g. maps and online tools),
• establishing a relationship with the Finds Liaison Officers ,
• recording of finds on the Portable Antiquities Scheme,
• cleaning and preserving finds and
• links with History and Archaeological groups.
• Following up on research after you have found few items  which they thmselves act as research material 

There are lots of ways to undertake research - the internet and especially YouTube is invaluable. There are several monthly issued Metal Detecting magazines which make fascinating reading (hard copy and online).

I look forward to supporting you .