Minecraft no route to host

Me and my cousin. Living in the same house same network we want to play minecraft but everytime i make a server and open to LAN. And try to connect it says no route to host. But also it is it suppose to give me like a IP address like. Port 5436? Or something we're playing on separate accounts. I tried everything we could connect to other servers but just not the ones that we're hosting. "java.connect falied or something? And it says no route to host even on his i tried redownloading java and everything. I'm not a big computer wiz so. Hopefully it won't be too. Hard to find a sulution.

The fastest way to connect with friends is using Hamachi. You would use the hamachi ip address.
This would let you skip everything else I'm saying as I go on to explain other troubleshoots.

You should make sure your firewall is open to the port 5436. Sometimes your firewall will block incoming connections. Including, you will need to open the port from your router or modem.
http://www.whatismyip.com/
This website will give you your public IP address. It is considered not safe to share your own to people you do not trust. By using this outer ip address your friend can join you.