The easiest way to get started is with a pencil, a sheet of paper and yourself! Note down your name along with when and where you were born. Do you then have any siblings, a partner or children that you can write down these same details for? From there you can work backwards to your parents and any aunties and uncles, then grandparents and so on. A quick WhatsApp message to various members of the family might even help you fill in some blanks.
If you want to do something a little fancier and are happy to get a bit more technical, then there are a variety of online resources that you can use to build a more complete visual picture of your own family tree. Perhaps the most well known is Ancestry.co.uk
where you can not only create your own family tree, but if you are wanting to delve a bit deeper (and spend a bit of money) then you can search birth, marriage and death records to help link up family connections - you can even send off a DNA sample to find out more about own heritage!
Ancestry is not the only site that offers this service, and there are a number of others you could turn to; it all just comes down to preference. Find My Past
has probably the nicest looking family tree builder which can be used for free, and again they do offer a subscription service which is cheaper but not as extensive as that of Ancestry. Family Search
is a completely free website as far as I can tell, and as well as their easy to use family tree builder, you can also search their records to find other family members as long as you have a few details to go on.