たい is a hand reaching out of you

Where the picture shows up in たい

1. 1

   the hand reaching now

   今日は早く帰りたいです。

   kyō wa hayaku kaeritai desu

   I want to go home early today.

2. 2

   what the hand grabs

   冷たい水が飲みたい。

   tsumetai mizu ga nomitai

   I want a drink of cold water.

   Before たい, が sounds more natural than を: the noun is what pulls you, not what you act on.

3. 3

   a hand held out gently

   ちょっと相談したいんですが。

   chotto sōdan shitai n desu ga

   There's something I'd like to ask you about.

   To a superior, したいんですが lands softer than したいです.

4. 4

   a hand you reached long ago

   昔は看護師になりたかったです。

   mukashi wa kangoshi ni naritakatta desu

   I wanted to be a nurse back then.

5. 5

   pulling the hand back

   今日はあまり残業したくないです。

   kyō wa amari zangyō shitakunai desu

   I'd rather not work overtime today.