A simple Makefile

    CC  =   gcc

    NAME    =   name_of_binary

    CFLAGS  =    -Wpedantic -pedantic-errors -w  -Wextra  -Wall -Iinclude

    SRC =   core/my_printf.c \
            core/save_printf.c \
        src/my_putstr.c \
            src/my_putchar.c    \
                src/my_strlen.c \
                main.c

    OBJ =   $(SRC:.c=.o)

    all:    $(NAME)

    $(NAME):    $(OBJ)
        $(CC) -c $(OBJ)
        ar rc $(NAME) $(OBJ)

    clean:
        rm -f $(OBJ)

    fclean: clean
        rm -f $(NAME)

    re: fclean all

    .PHONY: fclean clean re

---

Graphical Makefile Template

In this template I have a folder named src where is located all my .c file except the main.c which is root located. The $(shell find src/ -name '.c') means to Makefile to find all the .c files which are located in the folder src* including all the sub directory inside it.

    CC  =   gcc

    CSFML   +=  -lcsfml-graphics -lcsfml-window -lcsfml-audio -lcsfml-system

    CFLAGS  +=  -Wpedantic -pedantic-errors -w  -Wextra  -Wall $(CSFML) -Iinc

    NAME    =   name_of_the_binary

    SRC =   $(shell find src/ -name '*.c')\
        main.c

    OBJ =   $(SRC:.c=.o)

    all:    $(NAME)

    $(NAME):    $(OBJ)
        $(CC) $(CFLAGS) $(OBJ) $(LIB) -o $(NAME) 
        rm -f $(OBJ) *~

    clean:
        rm -f src/*.o
        rm -f *~ core/*~ inc/*~ src/*~

    fclean: clean
        rm -f $(NAME)
        rm -f a.out src/a.out core/a.out a.out

    re: fclean all

    .PHONY: fclean  clean   re

Some useful flags and possibilities of customs makefile you can use