explain that we need docker (yes, really)

and switch from 'curl' to 'wget' for installing weave, since the
latter is more widely installed. Also, make root use during that more
explicit.

README.md

@@ -13,14 +13,17 @@ multiple containers, running anywhere.
 
 ## Installation
 
-Each host needs to have `weave` from the `weaver` sub-directory
-installed in the root user's path, e.g.
+To run weave on a host, you need to install...
 
-    host# curl https://raw.githubusercontent.com/zettio/weave/master/weaver/weave \
-          > /usr/local/bin/weave; chmod a+x /usr/local/bin/weave
+1. docker. We've tested with version 1.1.0 through 1.2.0, but other
+   versions should work too.
+2. weave. Install this with
 
-We also need `ethtool`. On most systems that is installed already; if
-not then grab it via your favourite package manager.
+        sudo wget -O /usr/local/bin/weave https://raw.githubusercontent.com/zettio/weave/master/weaver/weave
+        sudo chmod a+x /usr/local/bin/weave
+
+3. ethtool. On many systems that is installed already; if not then
+grab it via your favourite package manager.
 
 ## Example