Just do it! Put the words down on paper and go for it! It is helpful to get feedback from as many people as you can, recognising that friends and family will usually be kind, but also recognising that not everyone will like what you have written. Try to use criticism positively and not let it deter you. It's important to try to take an objective view of your own writing - which is not always easy - but if you have enjoyed writing it, then it's likely that there will be others who will enjoy reading it.