diff --git a/README.md b/README.md
index 0c2597e..90d1a5a 100644
--- a/README.md
+++ b/README.md
@@ -1,8 +1,10 @@
 The code uses two approaches to fit the experimental data with gamma distribution . 
 
 1) find a0 + a2*P2 + a4*P4, then use a0 to search for mini delta, the mixing ratio
-2) fit the a0 and delta directly .
+2) fit the a0, delta, and sigma simultaniously.
 
-#simply make
+#simply make to compile the ad++.cpp
 
-The settings and data are hard coded. 
\ No newline at end of file
+The settings and data are hard coded.
+
+#or, using root, load ad++.h as macro