Newcastle host Everton at St James' Park on Saturday on the back of reaching the Champions League round of 16 after their playoff triumph against Qarabag.
Asked about facing the Toffees, Howe began: "Difficult game for us. Our defensive mentality has to be improved.
"It is a big game for us. Everton have done well on their travels; their away form has been good.
"David’s (Moyes) team is always difficult to score against. Our attacking play has to be really good, and our defensive mentality has to improve.
"It is amazing to be back at home. We have to build our rhythm back. It was not the performance we wanted, but the result we needed against Qarabag."
Newcastle meet Everton, sitting in 12th position, below the Toffees, who are ninth.
Unsettling our players?
Before tomorrow's clash, Newcastle will learn who they will face in the Champions League later today.
Asked about a preference, Howe said: "Whoever we get will be mouth-watering for us."
Meanwhile, Howe was also asked about this morning's press reports of Arsenal leading Manchester United and Liverpool in the race for Anthony Gordon.
Asked if there's a campaign being run against Newcastle to unsettle their best players, the Toon manager replied: "You tell me. It is your industry who is creating those stories. The players need to be robust.
"I have seen a good response from everybody - there is a really good feeling among the players. The feeling is high."
He also said: "In the age we’re at, there is always rumour and speculation.
"I don’t see probably 90% of it. It comes with the territory of being a top player. You have got to put it out of your brain and focus on the football.
"I have not seen the story, so it is news to me.
"It is sort of your industry creating those stories. I am slightly secluded to it – if you don’t read it, you don’t know who is being linked with who.
"I think it is irrelevant really – it is how the players react to that. I think they will become robust enough to ignore it and concentrate on playing."
Miley and Livramento updates
Howe also delivered updates on midfielder Lewis Miley and full-back Tino Livramento, admitting both youngsters may not be seen until well into next month.
On Livramento, Howe said: "Tino will be early March, he has done really well. He is back, not with us; he has been running separately."
And on Miley, who has worn the captain's armband this season, the manager added: "We have to be careful with Lewis, he has had a couple of injections, we are looking at a couple of weeks for him.
"If we don’t get the management of this injury right, he could be out for the season."