Practice is necessary, sure. But there's a tip concerning spelling that can be used if understood how it works.
Did you ever think why some letters are extended up- or downwards? If letters had been the same size all over a writing there would have been some tension growing: in your hand - while you are writing, and in your eyes - while you are reading the message.
Our behavior, all our habits are rhythmical in nature, and extended elements establish the rhythm of writing... unless you write in separate letters. Write a whole word as one symbol and then "dot the 'i's and cross the 't's" with a backward movement of your hand. Don't write a word letter by letter - try to remember the whole word; and don't look at the sample word while writing it - check mistakes afterwards, when the word has been written. Use the extended elements as the rhythmical basis of your writing. Switch on some rhythm or music if you feel like it.