Splitting A Comma Delimited String

I have a string like say: '3:4:5:4,2:4:1,4:1:2:5:2'. Now I need to split the substrings delimited by commas. So my final output shall be

3:4:5:4
2:4:1
4:1:2:5:2


I did write a piece of code to achieve the same, but I feel its not so efficient. Can anyone suggest me a better way, if any? My code is as follows:

Declare @person as varchar(255), @cnt smallint,@loc smallint,@prevloc smallint, @str varchar(255)
Select @prevloc=0,@loc=1,@cnt=1,@person = '3:4:5:4,2:4:1,4:1:2:5:2'
While @loc != 0
begin
set @prevloc=(case when @loc = 1 then 0 else @loc end) +1
set @loc = charindex(',',@person,@loc+1)
Set @str = substring(@person,@prevloc,(Case when @loc = 0 then len(@person) - @prevloc + 1 else @loc - @prevloc end))
print 'String = ' + @Str
set @cnt=@cnt+1
end

RESULT
------
String = 3:4:5:4
String = 2:4:1
String = 4:1:2:5:2


Note: My actual purpose is to also sub split it again with ':' delimiter too. So looking for an efficient code.