This is part of my territory: I used to live in Attenborough, and I cut my unicycling teeth riding around the nature reserve 21 years ago. I now live in Carlton, and in the summer I often ride along the river as far as Long Eaton and Sawley.
If you are collecting for charity, you will need a collecting permit. This is not optional. Local authorities have a responsibility to control how many different charities and organisations are collecting in a given area.
Charity collectors, although they mean well, can be regarded as a nuisance. If there are too many, each volunteer collects very little. If the Salvation Army or PDSA is having a carefully organised flag day, having applied for the proper permits, they will be entitled to be cheesed off if you just turn up on their patch with a bucket.
There are also rules about collecting in sealed containers, and having the collections audited. This may sound daft, but unfortunately not everyone is honest. Any crook could jangle a box marked “For Cancer” then spend the money on cigarettes.
(See what I did there?)
And if you are going to collect for a recognised charity, you need to liaise with them. You will need their permission if you’re going to use their name and their logo.
Then there is safety and public nuisance. Public buildings, walls and steps are not yours to ride and grind on. You may get away with it “within reason” but if 20 people turn up and start doing it, you should be stopped.
I am all in favour of your idea to use your unicycling to raise money for a good cause. A safer idea is to organise a sponsored ride, or a sponsored uni-hockey game or something like that.
If you want a route for a 5-10 mile ride, you can cut through to the river near to McDonalds on the LE to Beeston Road and ride downstream (river on your right) through or round Attenborough Nature Reserve, through to Beeston marina, and if you like, right down the canal or the river almost to Trent Bridge. In the other direction, it is easy to get to Sawley Marina, and then there is a maze of narrow empty lanes as far as Kegworth. This is all challenging and interesting riding, and achievable on a 20 or a 24.
Alternatively the canal that runs alongside Tamworth Road will give you a 20 mile out and back route. I did a 24 mile round trip up and down that canal on a 24 a few years back.
If you are determined to do trials, I think you’d be well advised to get permission to use private land (a large garden, sports field, school yard, etc.) and pallets and prepared obstacles.
I’d be happy to give advice on routes for rides. I might even be persuaded to pretend to be a responsible adult for a trials event, but not in May or June as it’s the middle of the Morris dancing season.