I usually use a stepladder, but... it wobbles and it's scary... so I want you to hold it for me.
Literal
Usually [topic-は] stepladder [obj-を] using [copula-んですけど]... wobbles scary... [because-だから] holding [want-ていて欲しい] [copula-んです].
脚立 (きゃたつ) 'stepladder' is a practical household word. 揺れて怖くて chains two te-forms — 'it shakes AND it's scary.' 押さえていてほしい 'I want you to be holding it' stacks progressive ~ていて + ほしい. The trailing ・・・ pauses create a nervous, hesitant speech rhythm — someone asking for help while embarrassed.