I have found following these below steps to be useful for this.
1. Mastering CVC words and word families. By starting with sounding out CVC words (cat, dog, lip etc),the learner develops phonemic awareness and gradually with practice becomes confident with individual sounds and blending them together to form words. Then introduce word families (cat, rat, hat etc) to familiarise them with common phonemic patterns.
2. Introduce common words (an, the, and, is, you etc) that don’t follow phonetic rules to build sight word recognition. This will help with fluency in reading and understanding basic sentence structures.
3. Then move onto helping learners create very simple sentences using CVC words and sight words. (The dog sat.; I see a rat.) This can be reinforced with the help of pictures and flashcards.
4. The introductory sentences should follow a basic structure (Subject + Verb + Object or Subject + Verb + Prepositional Phrase). Provide scaffolding; use exercises like Fill in the blanks or Complete the sentence to get them familiarised.
5. Once the basic structure is learnt, introduce adjectives and gradually progress to simple connectors (and, but, and because) to help them move on to forming longer sentences.
6. Next move on to introductory punctuations and capitalisations (full stop, comma, question marks).
Connect the learner to what they see around them and their interests. This will help the learner gain better context. (Ex: I play with my dog. I have a red hat.) Provide prompt questions (What did you do today?; What do you see outside?) to encourage them to express their thoughts.
With gradual practice and with the aid of interactive activities, the learner should be able to make this progress.