Zenfone 6: update install instructions

Change-Id: I0058c21578f90cdd35593061fc97ff443fee6ecb
diff --git a/_asus/asuszenfone62019.markdown b/_asus/asuszenfone62019.markdown
index 271606b..d380968 100644
--- a/_asus/asuszenfone62019.markdown
+++ b/_asus/asuszenfone62019.markdown
@@ -30,5 +30,6 @@
 
 This will allow you to install the permanent version. Download the latest image from the download mirros specified above. Next use MTP to put it on /sdcard/.
 
-Once the image is on the phone, go to Install->Install Image and select the image you pushed to /sdcard/. TWRP will repack your ramdisk and permanently install
-the image to your boot_a and boot_b partition. Currently there is no official support for an installer zip to perform these actions.
+Once the image is on the phone, go to Install->Install Image and select the image you pushed to /sdcard/. Make sure to choose Install Recovery Ramdisk and not boot.
+TWRP will repack your ramdisk and permanently install the image to your boot_a and boot_b partition.
+Currently there is no official support for an installer zip to perform these actions.