Listen to the Welsh CDs and get familiar with the language. Get the CDs from any trusted supplier or download audio from the Internet. Listen online, if possible, to daily news being read in Welsh, and try linking the words being repeated often with the pictures being shown; you can also get news tapes from a library.
Get a Welsh guide book and go through the alphabet. The Welsh guide book shows an overview of the Welsh language and how it is spoken or written, giving examples after each lesson. Use the Welsh-English dictionary, which also which gives translations from Welsh to English and defines the words in English. Note the additional letters with vowels; for example, Welsh vowels include A,E,I,U,O,W,Y; the letters W and Y have been added compared to the common English vowels. Learn the different pronunciations of the letters; for example, "C" is always pronounced as in "cat" and never as in "since." Read the examples given after each word and note the way they are used in different sentences.
Note patterns that develop when reviewing how the words are used in different forms. This makes it easier to construct your own sentences. Formulate your own examples and use the guide book to confirm that they are right. Take your written sentences to a Welsh speaker or Welsh lecturer and let that person confirm whether you are on the right path. Writing the language is an effective way to learn how to read the language fluently.
Visit a school offering Welsh courses and get guidance on books that can be helpful in your endeavor. Read multiple recommended books.