The basic advice is to be vigilant, starting with prevention by assessing how likely you are to encounter insects on a particular walk and protecting yourself by covering up appropriately and/or using insect repellent. Then after a walk, check yourself (and any pets) for ticks, carefully remove any you find preferably with a specially-designed tick removal tool, or fine pointed tweezers as close to the skin as possible. Avoid squashing the tick body. If you show any symptoms seek medical advice.
Insects on walks at best are an irritation, but can also be carriers of deadly diseases, even in the UK. Scottish midges can make a walk in the glens very unpleasant, but a tick bite can lead to Lyme Disease and other dangerous infections. The Ramblers’ website gives some sensible advice at http://www.ramblers.org.uk/advice/safety/insects.aspx, with a helpful link to the Lyme Disease Society. There is also a good fact sheet at https://www.gov.uk/government/publications/tick-bite-risks-and-prevention-of-lyme-disease.