You can try by yourself, but the problem is, very few people will come to see.
The adventage of finding a agent:
1) their experience
2) a broad range of potential buyers
3) they take care of paper works for you, so you have no legal problem
4) many many more...
The adventage of selling by yourself:
1) Save the commision, but are you sure you can save 5%? Maybe your house will not be sold (so 0%), or sold at a much cheaper price (-x%).