The 4 non-SPI pins are defined in epdif.h file:
#define RST_PIN         8
#define DC_PIN          9
#define CS_PIN          10
#define BUSY_PIN        7
The 2 SPI pins for Arduino UNO are defined as:
MOSI  11
MISO  12  
SCK   13
#include <SPI.h>
#include "epd1in54.h"
#include "epdpaint.h"
#define COLORED     0
#define UNCOLORED   1
unsigned char image[1024];
Paint paint(image, 0, 0);
Epd epd;
void setup() {
  Serial.begin(9600);
  if (epd.Init(lut_full_update) != 0) {
      Serial.print("e-Paper init failed");
      return;
  }
  epd.ClearFrameMemory(0xFF);
  epd.DisplayFrame();
  epd.ClearFrameMemory(0xFF);
  epd.DisplayFrame();
  paint.SetRotate(ROTATE_0);
  paint.SetWidth(200);
  paint.SetHeight(24);
  paint.Clear(UNCOLORED);
  paint.DrawStringAt(10, 4, "Hello world!", &Font16, COLORED);
  epd.SetFrameMemory(paint.GetImage(), 0, 10, paint.GetWidth(), paint.GetHeight());
  paint.Clear(UNCOLORED);
  paint.DrawStringAt(10, 4, "e-Paper+UNO", &Font16, COLORED);
  epd.SetFrameMemory(paint.GetImage(), 0, 30, paint.GetWidth(), paint.GetHeight());
  epd.DisplayFrame();
  delay(2000);
  epd.Sleep();
}
void loop() { }BOARD?=arduino:avr:uno
PORT?=/dev/cu.usbmodem14*
.PHONY: default lint all flash clean
default: all flash clean
lint:
	cpplint --extensions=ino --filter=-legal/copyright *.ino
all:
	arduino-cli compile --fqbn $(BOARD) ./
flash:
	arduino-cli upload -p $(PORT) --fqbn $(BOARD) ./
clean:
	rm -f .*.hex
	rm -f .*.elf