Given list is [1,2,3,4,"a","b"] append each elements datatypes to separate lists.

Sure, here is the step by step solution:

1. First, initialize three empty lists for integers, strings, and others.

int_list = []
str_list = []
other_list = []

2. Next, iterate over the given list and check the datatype of each element. If the datatype is integer, append it to the integer list. If it's a string, append it to the string list. If it's neither, append it to the other list.

given_list = [1,2,3,4,"a","b"]
for i in given_list:
    if type(i) == int:
        int_list.append(i)
    elif type(i) == str:
        str_list.append(i)
    else:
        other_list.append(i)

3. Finally, print the three lists to check the result.

print("Integer List:", int_list)
print("String List:", str_list)
print("Other List:", other_list)

When you run this code, it will separate the elements of the given list into three lists based on their datatypes.