week 1

README.md

@@ -26,7 +26,9 @@ I set up trays for Severin, Timo and Matthieu on top of the letterboxes on
 floor K.
 
 #### Exercise sheet assignments
-* Week 1. **Cyril**. Circulate Fri 12 Sep. Upload Mon 15 Sep. Deposit Fri 19 Sep (noon).
+* Week 1. **Cyril**. Circulate Fri 12 Sep. Upload Mon 15 Sep.
+  Deposit Fri 19 Sep (noon). The first sheet is a practice sheet and should not
+  be entered in the system.
 * Week 2. **Alex**. Circulate Tue 16 Sep. Upload Thu 18 Sep. Deposit Thu 25 Sep (5pm).
 * Week 3. **Matthieu**. Circulate Tue 23 Sep. Upload Thu 25 Sep. Deposit Thu 2 Oct (5pm).
 * Week 4. **Timo**. Circulate Tue 30 Sep. Upload Thu 2 Oct. Deposit Thu 9 Oct (5pm).