Dictation.
In my first post I do not clarify all the different possibilities that might be in used to make up a bridge connection. And I did not know exactly what the original poster wanted. He said the connection without using ethernet, which is nearly impossible.
There is a mode where you can use several routers together without any ethernet connection, but he's not going to be able to do that because he has already a DSL modem that will not support that mode.
What you offered is not much different than what I suggested. In any case, somewhere there has to be an Ethernet connection between at least two routers. In the extreme case he might even have to go to using for routers connected together in a mix of wireless and Ethernet bridges. The original poster needs to clarify just how much effort is willing to put forth to achieve his goals. There are many ways to get the an Ethernet cable through a wall or under a rug or through a very small opening. But he indicated that he wants to go wireless without any Ethernet, which he did not clarify. If two routers are cooked together but it just 18 inches of Ethernet, it's still an Ethernet connection.
The mode that is not going to be able to move use is called the "Ad Doc " mode. Otherwise, anything else is going to require a little bit of Ethernet somewhere.
END. EDIT: There are many posts in the CH archives on "Wireless Bridge"
The OP needs to clarify exactly what he needs and can afford.