The clock and data pins are for your serial input. These can be controlled directly from the Arduino, just connect each to a digital out.  

For the data routine, according to the datasheet there is one start bit, followed by 35 data bits which correspond to the "Serial Input Sequence" table in your question.

Create a function in your "sketch" to control the serial loading, something like below - I haven't checked this code. You only need to call it whenever you want to update the display.   
You will have to replace the `set_data_pin` and `set_clock_pin` with the correct Arduino calls to whatever GPIO pins you have attached to the clock data pins on the display (I don't use Arduino so I don't know them) Same for the `delay_us` (microsecond delay) which can be adjusted to whatever timing you want up to 500kHz clock speed - you can add a define for the value to save changing each one.  
Each segment is shifted out MSB to LSB, which corresponds with A(MSB) to DP(LSB) for each input char: 

    void load_data(char seg1, char seg2, char seg3)
    {
        char i, temp;
        char position = 0;
    
        set_data_pin(1);  // clock start bit in
        set_clock_pin(1);
        delay_us(5);
        set_clock_pin(0);
    
        temp = seg1;
        while(i<8)
        {
            set_data_pin(temp & 0x80);  // set data pin
            set_clock_pin(1);
            delay_us(5);
            set_clock_pin(0);
            i++;
            temp = temp << i; // shift next bit out
        }
        
        temp = seg2;
        while(i<8)
        {
            set_data_pin(temp & 0x80);  // set data pin
            set_clock_pin(1);
            delay_us(5);
            set_clock_pin(0);
            i++;
            temp = temp << i; // shift next bit out
        }
     
        temp = seg3;
        while(i<8)
        {
            set_data_pin(temp & 0x80);  // set data pin
            set_clock_pin(1);
            delay_us(5);
            set_clock_pin(0);
            i++;
            temp = temp << i; // shift next bit out
        }
    
        // Last 11 bits - do something here if needed
        while(i<11)
        {
            set_data_pin(0);  // set data pin
            set_clock_pin(1);
            delay_us(5);
            set_clock_pin(0);
            i++;
        }
    }

**Connections**

* Connect the VDD pin to +5V, and the VSS pin to ground (0V) 
* Connect the VLED pins to +5V also. 
* Connect the DATA ENABLE pin low (i.e. to ground), as it is *active low*. 
* For Bits 25-34 pins, leave these unconnected if you don't wish to use them, otherwise you can use them as digital outputs. Don't tie them high or low (i.e. don't connect to +5V or ground)  
* For the BC (brightness control) pin, you can use just a resistor to fix the brightness, or a potentiometer and resistor to control the brightness of the display.   
To work out the value we can use the info in the datasheet: 
 1. The absolute maximum \$I_f\$ (forward current) for the display is 30mA (pg.2)
 2. The display current is typically 36 times larger than the current into the BC pin (pg. 4) and the maximum current into the BC pin is \$550\mu A\$ (pg.5)

 So with this info we can work out the best value for the pot. If we aim for a typical operating maximum of 20mA, then:  

     \$  \dfrac{+5V}{20mA / 36} = 9k\Omega \$   

 This is the minimum value of resistance we would use (connected between +5V and BC pin)  
 If we want to vary the current, say from \$10mA - 20mA\$, then we can add a \$250\Omega\$ pot in series with the resistor with it's wiper connected to one end (either end) Then the current varies between:

  \$ \dfrac{+5V}{250\Omega} = 20mA \$  

 with the pot turned fully the other way  

 \$ \dfrac{+5V}{250\Omega + 250\Omega} = 10mA \$