[DOCS] Improve the docs build instructions (#6173)

diff --git a/docs/README.txt b/docs/README.txt
index 03802fd..281cafa 100644 (file)
--- a/docs/README.txt
+++ b/docs/README.txt
@@ -5,7 +5,15 @@ This folder contains the source of TVM documents
 - A hosted version of doc is at https://tvm.apache.org/docs
 - pip install sphinx>=1.5.5 sphinx-gallery sphinx_rtd_theme matplotlib Image recommonmark "Pillow<7"
 - Build tvm first in the root folder.
-- To build locally, you need to enable USE_CUDA, USE_OPENCL, LLVM_CONFIG in config.cmake and then type "make html" in this folder.
+- Run the following command
+```bash
+TVM_TUTORIAL_EXEC_PATTERN=none make html
+```
+
+```TVM_TUTORIAL_EXEC_PATTERN=none``` skips the tutorial execution to make it work on most environment(e.g. Mac book).
+
+See also the instructions below to run a specific tutorial. Note that some of the tutorials need GPU support.
+
 
 Only Execute Specified Tutorials
 --------------------------------