To use double pronouns you substitute a noun for a pronoun. For example: Michael is giving the paper to Laura. Michael is giving the paper to her.
In Spanish the order in which double pronouns are used is different, but if you remember this formula, it will get easier: First comes IOP (indirect object pronoun), then comes the DOP (direct object pronoun) and lastly the verb. After this comes the rest of the sentence. To review this concept let's simplify: IOP+DOP+verb+ rest of the sentence.
La maestra se la se lo dio a él. The teacher gave it to him.
You will have to know how to use direct object pronouns and indirect object pronouns, and when you have both of these in one sentence, you will use the formula explained above to form your sentence. IOP – DOP – verb – rest of sentence.
You will need to remember that indirect object pronouns always go before the direct object pronouns when these are used in the same sentence.
Roberta le lee una revista a Margarita. Roberta reads a magazine to Margarita.
Roberta se la lee. Roberta reads it to her.
It is important to remember that unlike English, in Spanish the double object pronoun will be written before the verb and not after it.
The indirect object pronouns le and les get simplified when used with direct object pronouns. You will write se instead of le/les when it comes after lo, la, los, and las.
Le compré una cobija al perro. I bought a blanket for the dog
Se la compré.
When writing a sentence that has direct object pronouns and is negative, meaning the words (no, nunca, jamas) will always go before the object pronoun.
No te lo haré. I will not do it to you.
Jamás se lo daré. I will never give it to you.