diff --git a/2018/giles/README.md b/2018/giles/README.md
index 7bf2246c6..2558a68c6 100644
--- a/2018/giles/README.md
+++ b/2018/giles/README.md
@@ -20,11 +20,16 @@ make
 
 ```sh
 ./prog ioccc.txt
+
 ./prog prog.c
+
 ./prog sand.txt
+
 ./prog sand.alt.txt
 ```
 
+NOTE: these invocations will take quite some time to finish.
+
 
 ## Judges' remarks: