Update README.md

README.md

 # Conda recipe for building VTK 7
 
-# Instructions for use
+## Instructions for use
+
 1. Install miniconda
 2. Update conda
   `conda update conda`
@@ -12,11 +13,18 @@
   `git clone https://git.fmrib.ox.ac.uk/fsl/conda_vtk_recipe`
 6. On Centos:
   `for i in conda_vtk_recipe; do yum -y install $i; done`
-7. On macOS install the SDK you wish to have as the earliest supported release:
-  1. SDKs are available here https://github.com/phracker/MacOSX-SDKs/releases
-  2. Download the required version, e.g. MacOSX10.9.sdk.tar.xz
-  3. Unpack this to an appropriate location
 7. Make the jsoncpp project available:
-  `conda config --add channels https://fsl.fmrib.ox.ac.uk/fsldownloads/fslconda`
-8. 
-  
\ No newline at end of file
+  `conda config --add channels \
+https://fsl.fmrib.ox.ac.uk/fsldownloads/fslconda/channel/`
+8. Ensure that zlib-devel is **not** installed (this causes cmake issues with 
+using the conda provided zlib
+  `yum remove zlib-devel`
+9. Create build/test environment
+  `conda create -n vtk_test python=3.5`
+10. Build
+  `conda build conda_vtk_recipe`
+11. Upload the generated tar.bz2 file (path is revealed in the last few lines of
+the build) to the web server (use the channel/osx-64 or channel/linux-64
+as appropriate) and then run:
+  `conda index channels/*`
+on the web server in the parent.
\ No newline at end of file