The rate at which hair grows is genetically determined, and there's no product that will make hair grow faster. There's no 'easy' and 'quickly' - just patience and a bit of extra effort.
You might want to find a mild shampoo and a good conditioner that works for your hair type and avoid damaging it in a way that would lead to breaks or the hair falling out. Perms, dying hair with a high volume developer (like 'bleach blonde' colors), blow drying at high heat, and lots of sun exposure can make hair brittle.
Also, find a hairdresser who can tip off the ends every few weeks (sometimes called 'filing' - as opposed to 'trimming'). This can keep your hair looking nice even during awkward transition phases.