It's certainly fairly easy to cycle around the country. If you make sure you're not cycling at night or in the rain you should be ok. If you are walking try to do at least 10 miles a day or you won't get anywhere but even then I would suggest getting public transport out of the larger cities and towns. Hitching is always an option. As well as the Youth Hostel Association and the YMCA there is also a network of backpackers hostels which are often even cheaper.