Adds instructions to README

Author: JoseAlcerreca

Diff for: README.md

@@ -1,6 +1,46 @@
 Android Dev Summit 2022 Speed Challenge
 ==================
 
+# Instructions for contestants
+
+1. Clone repository
+
+2. Start coding!
+Check the local tests in `test/`. Do not modify the tests!
+
+3. Run tests locally
+Make all tests in `app/test/java` pass.
+
+4. Do not send PRs to the repo!
+
+# Instructions for hosts
+
+1. Create a couple of slides explaining the goal of the challenge and showing a screenshot of the app.
+1. Show the first hint on screen and drop a new one every ~5 minutes.
+2. Make sure contestants don't modify the tests instead of the code under test!
+
+## Hints
+
+### Test order
+`LocationScreenTest`
+`LocationViewModelTest`
+`UiLayerTest`
+`LocationConfigChangeTest`
+
+### LocationScreenTest
+Fix hardcoded title in `TopAppBar`
+Swap IDs in left/right icons
+
+### LocationViewModelTest
+Catch error in `LocationViewModel`'s Flow (don't forget to emit it)
+
+### UiLayerTest
+`LocationScreenForecast`: iterate on `forecast.forecastWeek` and create multiple rows in a column.
+
+### LocationConfigChangeTest
+expandedDays should be saveable (look for `indexSaver`!)
+
+
 # License
 
 Now in Android is distributed under the terms of the Apache License (Version 2.0). See the