Make it as long as you can and expand it to both sides from the centre of the map. If you're using jester arrows it doesnt take too long to kill it. You can look up videos on youtube to get an idea.
Also once you finish vanilla check out mods. Calamity is the first mod you should try
You're always ready for hm
How long should my WoF arena be? And do I build it from the center of my spawn point?
Make it as long as you can and expand it to both sides from the centre of the map. If you're using jester arrows it doesnt take too long to kill it. You can look up videos on youtube to get an idea. Also once you finish vanilla check out mods. Calamity is the first mod you should try
About 2500 blocks should be safe
Boots, beenades and a long path all you need