diff --git a/README.md b/README.md
index 747b369..aaef3de 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # Introduction
 
-The FSUDAQ is a GUI, supports 1 CAEN x725 and x730 digitizer with either DPP-PHA or DPP-PSD firmware. It uses the CEAN ROOT for the Graphical Interface. 
+The FSUDAQ is a GUI, supports One (for now) CAEN x725 and x730 digitizer with either DPP-PHA or DPP-PSD firmware. It uses the CEAN ROOT for the Graphical Interface. 
 
 ## Required Library
 
@@ -16,7 +16,7 @@ FSUDAQ \
 ├── Analysis \
 ├── DAQ \
 ├── elogText.txt \
-├── (Symbolic link to data folder) \
+├── (Symbolic link to experiment folder) \
 │   ├── data \
 │   │   └── *.fsu \
 │   ├── FSUDAQ.sh \
@@ -42,7 +42,7 @@ The rest of the files are for the GUI.
 
 The Analysis folder stores all online analysis codes.
 
-User should also make a symbolic link to the data folder.
+User should also make a symbolic link to the experiment folder.
 
 The FSUDAQ.sh will be created when running the FSUDAQ for the 1st time. It stored the program settings. 
 
@@ -56,4 +56,35 @@ Go to the DAQ folder:
 
 It will produce an executable FSUDAQ under the FSUDAQ, and FSUDAQDict_rdict.pcm.
 
+# Usage
 
+The FSUDAQ can be use as 2 ways. With digitizer open, run and take data, Without Digitizer open, open setting file and change it.
+
+## Setup experiment folders
+
+This can be done in 2 ways :
+
+1. Using FSQDAQ. once the FSQDAQ run, it will create the FSUDAQ.sh if not exist. From the menu -> Settings -> Program Settings
+2. Edit the FSUDAQ.sh
+
+The data folder can be inside FSUDAQ folder or anywhere.
+
+## Open digitizers
+
+Simply press the "Open Digitizers" button from the FSUDAQ. It wll scan all 4 ports of the fiber optics cards and 3 boards for each port. User can modify the MaxNBoard and MaxNPort in the code and re-compile.
+
+When a digitizer is found, connection will be established. And setting files will be created at the settings folder inside the experiment folder with filename setting_XXX.bin, where XXX is the board serial number. If setting file is found, the setting will be use and program the digitizer. 
+
+### After opened digitizer
+
+Once at least one digitizer is connected. The Board Setting and Channel Setting are avalible. 
+
+1. plot a single trace
+2. Continue run the digitizer without taking data. Can plot energy spectrum, count, or traces
+3. Take data. This will only take data, fast scanning the data, and dump it to *.fsu file. Files size limit is 2 GB.
+
+## Open *.bin setting file
+
+If no digitizer is open, user can open a setting file. once the setting file is open, the Board setting and Channel setting panels will open. User can change the settings.
+
+User can use the Save button at the board setting to save the setting file into text format. 
\ No newline at end of file