diff --git a/README.md b/README.md
index 53f614e..095efd6 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,20 @@
 # chromium-latest-linux
 Scripts to download and run the latest Linux build of Chromium.
+
+## Instructions
+
+### Running the scripts
+
+To run the scripts, use the following commands:
+
+```bash
+./run.sh
+```
+
+### Updating and running the scripts
+
+To update and run the scripts, use the following commands:
+
+```bash
+./update-and-run.sh
+```
diff --git a/run.sh b/run.sh
old mode 100755
new mode 100644
index 2d5f026..73fd843
--- a/run.sh
+++ b/run.sh
@@ -2,4 +2,9 @@
 
 BASEDIR=$(dirname $0)
 
+if [ ! -d "$BASEDIR/latest" ]; then
+  echo "The 'latest' directory does not exist. Please run update.sh first."
+  exit 1
+fi
+
 $BASEDIR/latest/chrome --user-data-dir="$BASEDIR/user-data-dir" $* &> /dev/null &
diff --git a/update.sh b/update.sh
old mode 100755
new mode 100644
index 6730185..779f458
--- a/update.sh
+++ b/update.sh
@@ -24,8 +24,14 @@ mkdir $REVISION
 pushd $REVISION
 curl -# $ZIP_URL > $ZIP_FILE
 echo "unzipping.."
+
+if ! command -v unzip &> /dev/null
+then
+    echo "unzip command could not be found. Please install unzip and try again."
+    exit
+fi
+
 unzip $ZIP_FILE
 popd
 rm -f ./latest
 ln -s $REVISION/chrome-linux/ ./latest
-