Interesting that people are suggesting that they get tick attachments quite high up on the body (including the nether regions!). Ticks prefer warm moist areas so will tend to migrate to places you'd rather they wouldn't be... I have only ever found them on my chest. I too am a magnet for any parasite!
As for removal I can only really speak with experience for animals. A couple of veterinary studies have compared various methods for tick removal and likelihood of complete removal (i.e. including the head) and post removal complications such as localised bacterial infection. The tick remover IDP has put a link to were shown to be most effective and safest in cats and dogs, with tweezers being least effective and more likely to leave the head in. I have always used an O-Tom tick remover on me and my patients as they are so easy to use. I think you get two or three sizes of remover in a packet, which means you get a small one which I find useful for removing the small ones before they've had a good feed. The key thing is to 'pull and twist' without squeezing the body. These removers stop the body from being squeezed.
We see a lot of hedgehogs brought in with loads of ticks. We used to bath them in olive oil or cooking oil as this helps to loosen them. However, this is no longer recommended as it may cause the tick to regurgitate its stomach contents, which increases the risk of tick-borne disease transmission. Manual removal is now recommended. This advice could be said for us too. Best not to put oil or vaseline on them.
There's quite a useful page and video on the BMC site, which is probably relevant to us fell runners:
https://www.thebmc.co.uk/get-ready-to-tackle-ticks.