Starting a new shell in a strcpy exploit using buffer overflow

Starting a new shell in a strcpy exploit using buffer overflow

I'm learning about buffer overflows and have this vulnerable code which I'm trying to start a shell from:

#include <string.h>

void myfunction(char *arg);

int main(int argc, char **argv)
{
     myfunction(argv[1]);
     return 0;
}

void myfunction(char *arg)
{
    char stuff[8];
    strcpy(stuff, arg);
} 

I used gdb to see the assembly code and I got the following info:

(gdb) disassemble main
Dump of assembler code for function main:
   0x08048434 <+0>:   push   %ebp
   0x08048435 <+1>:   mov    %esp,%ebp
   0x08048437 <+3>:   and    $0xfffffff0,%esp
   0x0804843a <+6>:   sub    $0x10,%esp
   0x0804843d <+9>:   mov    0xc(%ebp),%eax
   0x08048440 <+12>:  add    $0x4,%eax
   0x08048443 <+15>:  mov    (%eax),%eax
   0x08048445 <+17>:  mov    %eax,(%esp)
   0x08048448 <+20>:  call   0x8048454 <myfunction>
   0x0804844d <+25>:  mov    $0x0,%eax
   0x08048452 <+30>:  leave
   0x08048453 <+31>:  ret
End of assembler dump.

I'm unsure where to go from here. Any advice and walkthroughs would be very helpful.